I see what you mean, and I need to clarify, as, now looking at it, it isn’t so obvious.
What I meant to say is that there is a lot of variety in the types of instruments. For example, we have all sorts of basses, pads, strings, guitars, bass guitars, pluck and mallet things, keys, etc. However, many of the instruments in each of these subcategories sound similar to other instruments in the same subcategory.
Now, to your point, “the devs should just give out the sounds people want instead of making everyone jump through hoops to find some convoluted way to make it.”
Do the other programs and synthesizers you mention actually come with the sounds you want as presets? If so, that may be great for you, but more experienced producers will consider the presets that you used as “stock”. I can’t think of a single developer that provides every single preset you want, and if they do, you’re going to fall into the same rut eventually, when you want more advanced sounds than the stock presets: “Why can’t the devs just program the sounds in (insert synthesizer plugin) for me??”
Every single producer that I can think of has their own way of making their sounds, and from an outsider’s perspective, it looks like jumping through hoops, and “convoluted”. To the artist though, they know their sound in and out and don’t jump through hoops to make it.
Sounds aren’t everything, and Auxy is nowhere close to a synthesizer. You’re paying for the workflow and the availability of on-the-go music making. The app doesn’t claim to be an advanced DAW with every single feature or preset out there.
If you want a powerful synthesizer, you’re looking in the wrong place. If you want more presets that fit your needs, get a desktop DAW and plugins that have a larger preset library and click a few times.