My suggestion is that there would be a toggle containing two options on a studio you own:

• Have the studio be invite only (how studios currently work)
  

• Have the studio be joinable by anybody without needing an invite
  

Essentially making it so that anybody can join a studio.

Although, it does seem like the allowing anybody to add a project toggle is somewhat similar to this, but I feel like this option might reduce spam. Something that could be done is have a toggle for “Allow people outside of this studio to add projects”, so you can have anybody add projects, anybody who has joined the studio add projects, or only invited people add projects.

no support. if anyone could be curator they could easily wreak havoc and remove all projects and add their own. also what studio would require this?