I’m pretty sure they do it to fly under the radar, since mobile clients are far more dominant than smart TV applications.

And there’s also newpipe as an alternative to Vanced (or rather the other way around, I believe newpipe came earlier), and even a fork with sponsorblock integration. I personally vastly prefer them over vanced/revanced.

I’m using BubbleUPnp for screencasting.

You mean, only on Android TV. They don’t have a phone app, and explicitly stated they are not interested in developing one.

I simply don’t like them. There’s zero use case where I would consider a foldable phone superior, or even equivalent to a regular one.

Maybe the problem is on your computer’s end. Have you tried updating adb drivers and device-specific drivers (if any)? I’ve run into some issues with old adb drivers being present on the computer I was connecting to, even if the connection shouldn’t have been going through adb in the first place. But some identifier was acting up and causing misidentification of the device.