this is more prevalent in furry circles but not limited to there. when someone makes an original design for a species, they can decide whether to make it an open or closed species.
a closed species means that the creator forbids other people from creating characters from that species (though sometimes compliance rules are made instead). as you can guess, this is mostly unenforceable; some people respect those wishes, others don't. some will shun the latter, some others won't care.
btw I made it sound simple, but by god, the people of both sides often have very strong opinions about it
? the botw outfit is one of the costumes available for link in super smash bros ultimate, though, isn't it?