Apps that need SafetyNet to be in a particular state won't work. I never experienced the downside, even with my smaller bank's app, it works seamlessly.
Although, keep in mind, this is subject to change. All they need to do is just introduce the requirement in an app update, and then you're screwed.
Software tamperproofing. Or, at least an attempt to it. Apps can request the info from Android: "hey, is this a legit Android system? Everything in factory condition?" and this mechanism would respond. Some apps request this in the name of security. In an attempt to ensure that the user and their data via the app are safe.
Normal, unmodified Android systems report back that they are untouched. The system detects LineageOS, /e/OS, Graphene etc as modifications though, so then it reports that the system is compromised. As an option, it can be hacked, so it reports A-OK even on a modified phone - but this hack is prone to breaking, and not the easiest to do to begin with.
It's not straightforward which apps need this thing. I found a compilation here:
Although, keep in mind, this is subject to change. All they need to do is just introduce the requirement in an app update, and then you're screwed.