The block system is a great way to protect yourself from a harassing user, but there's still one component that makes the system noticeably less effective- as of right now, a blocked user can enter the same world as you without your knowledge.
This can lead to some pretty awkward situations where people go "Why do you have this person blocked?" and VRChat drama comes back up. Here are three steps that I propose to fix this problem:
  1. Make it so that if a user creates an instance, that no one they've blocked can enter via someone else. This includes for Friends+ and Invite+ as well as Public.
  2. Make it so that if a user is in another user's instance and a user they've blocked is invited or joins, that they receive a popup notification letting them know that person has been invited to the world so they have ample time to leave if they so choose.
  3. Make it so that if a user requests an invite into another user's world, and someone they've blocked is present, that before that invite request goes out, they're made aware that a user they've blocked is present. (Even just a list of who's in the room for certain types of instances would be helpful here)
I think this would do a lot to cut down on unnecessary conflict, and still leaves the door open for two users to unblock if they feel the need to as they can do so via the social menu or by meeting in a mutual public/friends+/invite+ world after they've received that notification.