I think alts are responsible for most of the things that are wrong with this game. Choosing a certain character means nothing if you can make 10 more, each responsible for a different function.
You want a perfect fighter, born to kill type of guy? Ok, but you should accept the fact that you will suck basically at everything else. can't craft, heal, etc. and thats the way it should be instead of a game where you can do everything with enough amount of time. without alts, if you're a fighter you would need people who supply you with stimpacks, people who repair your guns etc and this would create a working economy. in such system smart people will not make war gods who can't wipe their own ass. people will make more balanced, interesting chars.
as for exploring the game and seeing it from different points of view: you dont need alts for that. if you're bored with one char you could delete it and start over.
The only problem in my opinion is that prohibiting alts would couse players to cheat and devs would have to stop improving the game and focus on preventing alts and banning people who use them