To me, it's not a slim reason. And this is coming from a person who loves driving manual transmission cars - there are MANY operations I do around my place where hydro is better, for example, loader work and rear blade work (where is is nice to have one hand on the wheel and the other available to operate the loader valve or the rockshaft lever).
Running a stump grinder - again, you need to have basically instant forward/backward control and need one hand on the wheel and one on the rockshaft lever.
Many times mowing requires being able to ease right up to an obstruction which is very easy with the hydro. Maneuvering in tight spaces, especially where you might need to use the brake while also edging ahead with the hydro pedal, such as trying to precisely move something with pallet forks.
If I was using a tractor for something like farming or mowing many acres at a time, or maybe just with the tractor sitting still using a
chipper, splitter or some such thing, yes, I might choose a gear tractor. Is a shuttle shift better than a gear tractor for frequent direction changes? Absolutely, but still not as convenient as a hydro in my opinion, especially if you need both hands free for other stuff.
Don't be sad about people choosing hydros - at least with tractors, they won't quit making gear drive tractors just because people like to buy hydros. Wish I could say the same about manual shift cars/trucks.