Ok, update, so there's actually not even any need for the Areas mod.
Just go into minetest.conf, go to "default_privs" and you can remove the interact privilege, so new players by default have a guest mode with no interaction ability.
Then you can just grant players the interact privilege by:
grant <player> interact".
What I'm also using is the Server News mod
Which I use for welcome info, and it has by default a "news_bypass" privilege. If you edit the lua file to remove the top part it registering that privilege, and you edit where that privilege gets used to the "interact" privilege, then you only need to assign users the interact privilege and bam that server news pop up on join will not show again unless you fo the "/news" command.
So that's one mod not needed now that worked that out.
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