The req isn't low, being a mentor is just a 'status' that the player can set. Doesn't mean you're the best player in the world, it just shows that you played the game a lot and it doesn't necessarily mean that the player is good either. But as always, the dungeons between 41/43 to 49, are >usually< plague with terrible players, let it be Tank,Healers or DPS.

Sure the req could be higher once stormblood gets release, but then what?

Up the limit on commendation? Ridiculous.
Add a 'playtime' req? Leave your PC/Console on 24/7 until you're set.
Like commendation, more dungeons/trials/raid done? Ridiculous.

All the things most of you guys ask more is just about 'play time'. Now, the people who talked about the achievment system coming into play, that could be worth it. But then again, if you played a lot, you should easily have over 5k if you played since 2.0 (or you live on the game).

No matter what happens to the mentor req, there will always be bad players, simple as that.