In theory, SafetyNet is meant to be an anti-abuse software that allows poorly made apps to "assess" the overall "integrity & security" (not necessarily root) of an Android device the app's on.
18/9/2024 Update : SafetyNet now deprecated & replaced with Play Integrity. Same shit, different name. Also focused on keeping Goolag's monopoly over Android.
For example, prior to Magisk 20.4, MagiskHide is enabled by default (and it works for basic attestation on both microG & GApps ROM at that time). Goolag enables hardware-based attestation (which for now is opportunistic - when possible, it'll do it), Magisk 20.4 (and beyond for now) is released with MagiskHide disabled, kdrag0n releases a module to bypass hardware attestation, and Goolag eventually makes hardware attestation mandatory, completely defeating this new fix & perhaps even block out PDA users without hardware attestation support.
A good example would be Pokemon Go. In a misguided attempt to block cheat abusers, they ended up also blocking legit users with unlocked bootloaders, custom ROMs, and/or root.
Another example would be banking apps (or money-related apps) - instead of trying to make good security measures for their customers, regardless of their device; they instead used DRM that blocks legit users running anything that's not stock ROM. However, nothing's preventing you from banking through the browser (assuming it's supported of course).
Here's an actually matching example - Netflix. They put DRM on the videos so that nobody from certain nations get to watch them without VPN (even with VPN, there's always a chance of Netflix blocking them), and DRM on the app (SafetyNet) so no actual users (not the "Netflix & chill" normie useds) get to use the app.