A different multiplayer question

[foggy flume]

I know that 4 players can play in one world. I also know that non-host players create a new character in that world that remain in that save file. Does that mean only those 4 people can ever play in that world? In other words, are there only 4 character spots in any one world?

[dusky remnant]

You can only have 4 players max in a coop world but they don't always have to be the same people