Fallout 76 can still be played by yourself. They’ve made that quite clear- it’s basically a fallout 4 co-op/multi expansion. They’re giving to people what they have wanted forever and that is to play Fo4 with their friends. The building of bases/community stuff it will all still be there from what I read.
Yes but in a world with no human NPCs. So just gouls and deathclaws and rad scoprions. Cool I guess. If you do come across humans, you aren't by yourself anymore, you're just alone because every human is a player and you might be about to die.
They've also said that you can't really choose your server so you you will get put in with randoms, not alone. Until they do private servers. So you can be the lone wanderer but I don't think it's true you can really play offline, by yourself. Just without friends.
A lot of people didn't like Fallout 4 because you couldn't really role play, you were in a preset role and you had to play it that way. if you wanted to be evil, too bad. This lets you be a raider and join a group of raiders if you want, then you can go grief other players all day and night. Or for a police faction and go fight raiders. Or be a trader. In principle all that's good but I'm jaded by other online games that just quickly devolved into "kill or be killed" games.