There's a wide range of ages when it comes to the Roblox generation and I speak from experience as a librarian having to shush both kids and teens for being too loud on the computers while playing.

You can remove someone from a Slack channel if a member is no longer involved in the conversation. It's easy to do so on desktop or mobile.

You can easily unblock someone on Houseparty should you have changed your mind about blocking the person.