I currently run Android 11, and I went through a while ago and disabled any CAs that were hinky or I didn't like what nation they were associated with. AFAICT, there was nothing at all that broke after I disabled so many of these trust anchors. I am not sure if the GP is saying that bundled root CAs can override OS-supplied trust anchors, particularly any which have been manually and administratively disabled, but that would be a disturbing, yet helpful, thing to know.