Flawed? Looks fine to me. In ye olde days there weren't really standards for app icons and they all did whatever they want, and the support is still there, it's just not a lot of app devs use "legacy" icons.
Lemmy is a reddit-like that redditors are migrating to because of reddit's recent decision to kill 3rd party like twitter did (and their piss poor management, also like twitter). as for why DEs don't tile windows, the world may never know.
Judging by the @s in your comment you are posting this from Mastodon, which severely bungles Lemmy threads. The OP is posting on a Linux community and has a problem that only tiling window managers can really solve, average users don't matter here.
Jerboa search only finds communities that at least 1 person on your instance subscribed to, to find new communities from other instances easily I like to use https://browse.feddit.de/
Then when you find a community, go to the web version of your instance (don't worry it's (mostly) mobile friendly) and type !name@instan.ce (don't forget the !) Then you can subscribe there. Close and reopen Jerboa and your new community will show up in the list. The Jerboa devs are working on fixing this.
I honestly prefer the older style where everyone did their own thing, but that's just my opinion.