@johnlitt @mngrif @freemo yes. There is an option to do so. You just can't do it on your own instance. If you choose the person where you have the FOLLOW button, there is a hamburger menu to the right of it. One of the options is to block a whole instance from which that person comes.

It is certainly up to you to curate your own feed. I would encourage you to block or silence at the finest level possible. I have yet to find an instance where "everyone" is problematic. But those are my opinions offered freely, and worth just as much :)