It is intentional as has already been said but people need to realise: just because you can play every job on the same character doesn't mean you can perfect every job. As far as I'm aware, FF14 is a lot more forgiving in this than most MMORPGs.

But is 15/15 that bad? No my friend is 15/15 and he does both jobs well, not "Amazing!! Dude I need you in my T5 static!!" but he does it well so if we need a magic DPS for anything outside of coil? we have it. Need a decent healer for primals etc? We have it! Or you could go 30/0, you'd be brilliant at 1 but less good at the other, I say less good but not bad. You can still be useful to your friends and be a utility player, if you are geared enough.

The system works as it was intended, make a choice, DPS, heal or a bit of both.

So far we only have 1 example of this but when new jobs are realised you will be making this decision multiple times for multiple classes.