I don't think that the fediverse is exclusively used by "older tech nerds", but as someone who matches all three points you mentioned... I must say, you're still a good observer. XD
But it's logical. The more experienced tech crowd is the starting point of it. They are the ones not only able to see the flaws of corporate platforms and complain about it, but also with the technical skillset to just say "Fuck this, we make our own.". If you're not into computer stuff, you simply won't be able to create and maintain an alternative. And it also takes at least a little bit of both life- and coding / web / tech experience to get to that point, so the age is also a given, at least for the initiators. Younger folks may like what's happening and be joining in. And Linux runs the web. It dominates the server space, so the people who are working with it might also use it in their private life. Some others simply enjoy their OS and software not being bloated corporate spyware for the advertisement industry. So they are attracted early as well.
Don't worry though. "Older tech nerds" are regular people, too - with other hobbies and preferences, things, pets and people in their life.
So the nature of the fediverse is... community. People stuff. And that is fully compatible with other demographics. If they have enough of the likes of Reddit and Meta, they will find a compatible alternative here for their needs.
But that doesn't mean the fediverse has to replace those big tech platforms. People have choice, you know. And things can coexist. I'm perfectly fine with the size of Lemmy's community. Reddit refugees are highly welcome, but I don't worry about the user count, as long as there is a reasonable amount of interaction.
I'm super torn on desktop environments. There simply are too many great choices! I like XFCE, KDE Plasma and the most recent Gnome versions - for different reasons. KDE is the perfect choice when you want the full shiny, modern, bling desktop and if you love to customize it in all kinds of ways that are possible out of the box. When I spend time with KDE, over the course of weeks, I keep constantly changing my wallpapers, themes, cursors, icons, colors, etc. - just for the sake of variety. With KDE, the desktop never gets boring.
BUT... I also love minimalism (to a tasteful, practical extent) and classic retro computing, as well as efficiency. That's why XFCE is very comfy to me. It only has the features you need, but still to the extent of a nice and fully featured desktop environment. Doesn't eat too many system resources, still can look very pretty with themes, does what it's supposed to. Very stable, too. There are times when KDE just feels cluttered and ... too much for me, then I retreat to XFCE.
I'm running Fedora Silverblue for quite a while now and although I always had my gripes about modern Gnome... after using it for a while, it really grew on me. Since version 42, modern Gnome really is going the right direction. It's nicely clean and readable, modern, performant, and once you get used to it, its different approach to the workflow really makes sense. The apps are lovely, they do one thing and do it well, and they're beautifully integrated in the same design language. There's a wonderful collection of apps called Gnome Circle, these are not developed directly by the Gnome team, but endorsed by them, as they're useful and integrate perfectly into the UI design language. There's some amazing tools in there! It all feels very unified, and with the Blur-my-shell extension, you don't need much else for a pretty look.
The only downside is that this clean look sometimes is achieved by cutting poweruser features, which can be frustrating when you bump into something you need to do, but the UI doesn't account for. For example, I have multiple bluetooth adapters in this PC and can't select which one to use. Still, great desktop.
I think you always need some amount of ram and cpu in a server... ;D
Well, it's a shame if those video calls aren't working nicely without some fiddling. I'll still set up a Nextcloud at some point, for all that other stuff like calendar, contacts, office, chat and file sync. Kinda enjoying the benefits of cloud synced data, but without a corporation hosting my information and selling me to the advertisement hyenas.
Nextcloud looks really great and it has a chat / video chat too, I want to give it a spin in the future, as it also allows you to self-host a lot of things that people usually outsource to Microsoft, Google or Apple.
Probably only relevant to German readers, I'm currently enjoying "Sanctum" from a series by Markus Heitz. He made a trilogy about werewolves and one about vampires, both are great if you're into spooky stuff, action and a bit of fictional violence. ;)
Personally, I think that the Judas trilogy (the one about vampires) is written slightly better and a more fluent story arc, so if you only would give one of them a try and you're not an absolute werewolf fan, I'd start with "Kinder des Judas".
I don't think that the fediverse is exclusively used by "older tech nerds", but as someone who matches all three points you mentioned... I must say, you're still a good observer. XD
But it's logical. The more experienced tech crowd is the starting point of it. They are the ones not only able to see the flaws of corporate platforms and complain about it, but also with the technical skillset to just say "Fuck this, we make our own.". If you're not into computer stuff, you simply won't be able to create and maintain an alternative. And it also takes at least a little bit of both life- and coding / web / tech experience to get to that point, so the age is also a given, at least for the initiators. Younger folks may like what's happening and be joining in. And Linux runs the web. It dominates the server space, so the people who are working with it might also use it in their private life. Some others simply enjoy their OS and software not being bloated corporate spyware for the advertisement industry. So they are attracted early as well.
Don't worry though. "Older tech nerds" are regular people, too - with other hobbies and preferences, things, pets and people in their life. So the nature of the fediverse is... community. People stuff. And that is fully compatible with other demographics. If they have enough of the likes of Reddit and Meta, they will find a compatible alternative here for their needs. But that doesn't mean the fediverse has to replace those big tech platforms. People have choice, you know. And things can coexist. I'm perfectly fine with the size of Lemmy's community. Reddit refugees are highly welcome, but I don't worry about the user count, as long as there is a reasonable amount of interaction.