The inconvenient truth here is also that following the system theme is an anti-feature for most apps. On the desktop, you want your app window to be recognizable at a glance, meaning the primary color should be the brand color, etc.

I currently have open Chrome, Spotify, Discord, Aseprite, and Zed. All of them look completely different, and that's actively helpful for me, the user.

It's nice to follow the system's light/dark setting, and obviously the behavior of basic UI controls should be unsurprising, but beyond that there's no point in "consistency".