Whilst, for me personally, it's not a big deal, as my character will be pretty much me, and I'm a typical short haired guy, if I wanted to recreate my mid 20's self, I'd be screwed, as I had quite long hair then (the whole surfer/extreme skier thing....). I probably would have been a little annoyed.
Really though, I can totally understand where this is coming from, especially from a character perspective, as someone may be roleplaying a Dothraki style, that doesn't cut their hair/beard/whatever unless they are defeated in battle/caught smuggling/find an alien ruin/whatever.
I really can't see the harm - even if it ends up being a Singapore Airlines style hairdo, where the long hair is tied up in a way that look neat, yet is clearly quite long if let out. There is no remlock/helmet issue there.
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