Please check what you're linking to before making posts.
Now you've made me hungry.
I agree with the other posts that you can either ask the user who is sending you invitations or unfollow the user who is doing so so they can stop spamming your messages. But ban a user just because they send you an invitation? Isn't that way too harsh? Scratch studios wouldn't even work anymore - because everyone that sends invitations will get banned! Scratch will be left with only, like, 20 million users instead of 57 by the end of the week that this gets implemented.
And why would the Scratch Team even have to continue putting the button in studios if people just get randomly banned for it? They could just remove the button - but that would be the end of studios, because you can't invite anyone - and there you go.
This suggestion would directly lead to the downfall of studios and a major part of the community, just because you decided it's annoying.