If you typed in sv_consistency 0 in the console and your friends or randoms still can't join, make sure they (including yourself) have custom server content set to none. this is located in options - multiplayer - custom server content. from what i saw after applying that, this wont get rid of content in modded or community servers. this will only make it so the game won't be stuck loading when joining a friend or joining a random person's game. i noticed this happens because of special/common infected mods i think. so make sure you all have that set to none along with sv_consistency 0 and im pretty sure yall should be good. you will still be able to see your own mods, your friends/randoms will also be able to see their own mods, so it won't be deleting/disabling anything. also i think typing the command cl_downloadfilter none in the console does the same thing but i never tested it out, someone said it in the comments.