I always disable it. Having everything using the same exact colour palette is boring/homogenized. The themed icons are even worse, simultaneously killing iconography art and making it much more difficult to differentiate between apps in the app drawer quickly.
https://www.xda-developers.com/material-you-monet-theme-engine/
Apparently it’s officially called material you, but that name is so stupid I think I’d prefer to call it by it’s code name too.
That’s stupid. Thank you for sharing.