If you are below a certain level, you shouldn't even be able to join in a fate, and instead the game should auto tele you back to your homepoint after 10-15 seconds of being inside the fate. It's really annoying on especially large encounters like Svara, Chimera, or Behemoth where the fate monster keeps phasing in and out because there are too many people, most of them being 10+ levels lower than the fate. Makes it really hard to get anything above bronze on a fate that I'm actually the right level for.