Some old video codecs were proprietary and had to be installed afterwards from a separate repository or package, that might be where that notion is coming from. That being said once the relevant codecs are installed (open-source or proprietary) things just work fine, or you could install VLC or mpv and just call it a day.
I know that feeling. I’m torn between Apple Music and Spotify myself. Spotify is just that much more convenient for me but at the same time, so is Apple Music…
Ehhh, even for that I’ve had issues, even before the API stuff. The solutions I came across either came from casual word of mouth on Discord, tutorials on GitHub or forums other than Reddit.
For near-guaranteed compatibility, there are dedicated manufacturers like System76 and Tuxedo. Framework also claims Linux compatibility but for set tested distros (Ubuntu and Fedora).
Generally, anything with Intel/AMD graphics and Intel Wifi is pretty much guaranteed to work in my experience. For laptops, high-DPI displays can be problematic but the fixes are on Wayland which is getting higher priority now.
I had to help a friend install the VMware kernel modules, since VMware is weird and VirtualBox sucks for virtualising Windows. I had to guide him through it step by step, making sure his commands were exact.
He’s only started using the terminal properly. Hell no, I’m not going to recommend Arch to him.