Hi medium-density, welcome to A2K.
I think there are a lot of ways to get around the "he" default. Even though it doesn't bother me that much I do see your point, and agree. I remember reading someplace about changes towards gender-neutral language having a real (positive) effect, but I don't remember enough about it to find it back right now.
I'm not sure what I usually do. I think I use "one" or "someone" fairly often. I'm sure I revert to "he" sometimes too when I mean people of either gender.
Basically, I wouldn't go so far as to say it's bad practice, as in I'll get mad at someone who does it, but I also think it's worth putting some effort into avoiding it, myself.