These are miui shenanigans. You can disable chrome in settings and set different browsers as default on most other Roms like oneui, stock android, realmeui, etc. Last time I used miui, I decided never again.
Why go through so much hassel? It’s the default system app. Many samsung services and app’s are likely hardcoded to use it for stuff like that. It also excels in certain tasks like bulk image moving, deleting compared to Google photos. You won’t get hurt just by having it installed.
You are better off using an open source app like Aegis, KeepassDX, among others.