That's half of the discussion here, is it just because everyone is doing it, so even a player who'd have a clearly better BH than his FH would still prefer playing FHs and lose points, but not turn around it?
There is nothing natural about it, it is as it is simply because the FH is the stronger, more precise and more regular shot. Maybe it's been built in the player that way since a child, but it is a fact imo.
Actually, biomechanically speaking, it's much more textile than the same shot from the backhand side. On the forehand, the hitting arm/shoulder goes back, encouraging rotation of the body through the swing, which makes the stroke much more fluid. On the backhand, whether one-handed or two-handed, you're inherently limited by the fact that your hitting arm has to go across and behind the body (shoulder stays forward), so weight transfer and foundation are more important to driving through the ball. These are more difficult to accomplish when moving around, and therefore away from the ball.
The principles about weight transfer and stability are some of the same reasons why you don't see open-stanced backhands as often as you do on a forehand (virtually all the time).
Here's a link on the bio-mechanics of either backhands:
The other thing, though, you hit on the head. It's not taught as much, even for kids/juniors who favor backhands, and I can say that from the perspective of a player and a coach. One of the reasons for that is because of the angles possible with a forehand that aren't accessible to a backhand (again because of the stroke design).
The actual illusion that makes some ppl even consider a BH would be better in general than a FH in ATP is because they instinctively compare the BH to other BHs and not to the FH itself.
The thing is, though, the forehand and backhand assume two very different roles for a typical player. The forehand is used much more proactively for various reasons, while the backhand is traditionally intended to endure more. To me, it's when the latter exceeds that mandate as a weapon that you can begin make an argument for superiority. Because a stable weapon beats a temperamental one every time, no matter how much more potential the latter should have.
Gasquet's backhand can reach over 100 MPH. He uses it as proactively (he hits inside-out BH's) as his forehand, and it's generally much more consistent and reliable. On what grounds is his forehand better?
Fish's forehand is rarely ever used as an offensive weapon, and it's much more prone to breaking down than his two-hander; ditto Cilic.
Even if we consider that their forehands are potentially greater, as you have insinuated, and I agree with that, at what point is that a reality for any of the players I just mentioned?