Did you unlock your bootloader? Some apps just scan for Google Play SafetyNet or in some other way to check whether you unlocked your bootloader or rooted and if they think you do they will vaguely state you are rooted.
Other's concern about your phone being infected are justified and I recommend you to try whether a dedicated root checking app thinks your phone is rooted. These usually don't lie.
Regarding your rooting situation I always rooted the lazy way. Renamed magisk.apk to magisk.zip, flashed it and it always worked for me. But I rooted only 2 phones in my life really and this is not the recommended method by magisk developer.
I am sorry. I went to a little rant, but I meant it rather funny even though I realize it feels aggressive 🤣. I am just enthusiastic about this topic even though I don't know that much.
You can with some tinkering. You can uninstall the default launcher with ADB shell and some Android TV show select launcher options when more than 1 is installed.
It's very fine unless you decide you just must and have to convert that audio to MP3 (the audio loses quality with every lossy compression), because you are an old boomer and other formats scare you even though almost all modern device can play OPUS or at least M4A or you are one of those people who call themselves "Audiophiles" to feel more special, but wouldn't recognize a shit if I played OPUS 192kbps on their 2000$ home audio setup instead of the 24 bit uncompressed FLAC that has over 30MB in size each. I have most of my library from YT Music which is ~128kbps OPUS and it has been transparent on all audio devices I have played it till now.
Some probably use an API of some sort, because SmartTube for Android TV even synchronises your watch history, subscriptions, you login with your google account etc...
You won't get video recommendations on your home feed (and maybe also other parts of youtube) if you have watch history disabled in your google account settings (you request google not to save your watch history).
I like ytdlnis more.