Your points are all entirely fair. It also surprises me how quite a few people don't get it.
And it's not that many requisites to fix it either.
A) don't break shit on updates. This is the worst thing that could happen.
B) There needs to be a clicky app store. Just one. No options. No pick your repos. No pick between flatpak and whatever else. Just a visual app store you click an app and it install. You click to remove it gets removed.
It's seriously not that much you'd think.
Having that said. If you do choose to endure through the learning curve. It's mostly worth it. But fuck. It's such a dumb self imposed learning curve.
Man I wish I had time to boot up a vm with a big distro, open both stores and try to install something, it's immediately obvious.
There's a reason everyone online says "oh yeah, the stores exist, i still use the terminal though"
They do not work.