You can always do that part after you beat the game yourself. It's not a big deal, it isn't a long game at all if you do only the required stuff.
I mean, I mentioned this before, but a first time playthrough will average out in 35 hours. If it's blind, you're not going to know what the required areas are, nor the fastest way to beat them. And even if you DO have foreknowledge, I think Jaded told me a speedy playthrough would probably be average in at 12 hours. I know that's about the length of the average game, maybe a little longer, but a 12 hour time investment is nothing to sneeze at. When I was younger, yeah, 12 hour games could be done in a day if I was really invested, because I had nothing else to do. Nowadays, between school, social obligations, extracurricular activities, looking for jobs, planning for my future, I have fairly little time to game, maybe a couple hours long sessions every few days. If I do more, I have to neglect one of those, which I'm willing to occasionally do, but I can't do it on the regular. I mean, I haven't played BB to finish off Larry, Orphan of Kos, and Gerhman and Moon Presence for the last few days because I have a whole bunch of tests this week I need to study for instead, when if I could, I'd probably could finish them all off in one sitting.
I like long games (provided they're not wasting my time, of course *glares at MGSV*), but they are officially a significant investment at this point in my life. Which is part of the reason that I find the idea of playing the game 4 times in all stat builds so you can experience it's complete content to be ludicrous. I have SO many other games to play, and SO MANY other media to consume. So this suggestion to just play the game again, and again, and again, just to get the relatively complete experience, which I feel should be available to everyone the first time around, is just something I cannot accept. It's fundamentally the wrong way to design games for me.
And please note that I say relatively complete. It'd be one thing if the game were withholding a few things, but you can miss such a significant amount of the game's content, you can't use the majority of the game's awesome weapons. That's insane to me. I can live with not fully realizing one stat, maybe 2, but when you lock me out of 75% of the game's weapons or withhold major areas, just so I can finish the game in a relatively quick manner, which isn't very quick on the whole in any case, that's when I get mad. I don't think that's fair at all, and when you layer on not knowing what the game holds later on on top of that, without the ability to go back and adjust your playstyle to your liking, that's just bullshit.