It depends. Children are naturally curious. I think it comes down to how you deal with that as a parent. Our son is interested in pretty much everything we do. As much as possible, we take the time to involve him. Tell him what's happening, why we're doing things a certain way, etc...
I assembled the NFC reader together with him, and he did question what it was for. Obviously he doesn't understand the technical details behind it, but he understand that the box recognizes the cards he put on top of it. That's enough for now. Maybe in the future I can dive a little bit deeper into it.
I agree that kids shouldn't spend a lot of time behind screens. But I disagree with the fact that 30 mins is too much.
Our oldest son watches TV while drinking milk. That's either first thing in the morning (while still being a bit sleepy and while we get his younger brother ready) or it's just before bed (when physically exhausted from playing all day).
I see some benefits to watching movies instead of TV shows. Watching a movie for 30min at a time, trains his ability to focus for longer periods of time. A skill that I highly value in this era of TikTok and 30 second attention spans. He also learns to follow a story, to have empathy with the characters, to see situations in which he hasn't found himself in yet, and so forth...
And yes, it's also convenient for us. During those 30min we can get his brother ready and dressed, make lunch, get ready ourselves, etc.
Ultimately, it's up to each parent to decide for themselves. What is an acceptable amount of screen time, and how do you spend times away from screens. For us, that's a little bit of TV in the mornings and evenings, and no screens in between.