You have conveniently forgotten to list how much unusable/me-too/buggy/harmful/hostile software exists in the paid-app stores.
In my opinion there hardly is any crap in FOSS utilities, instead there is elegance, scalability, stablilty and rock-solid design principles.
Now when I think about it, seems that FOSS fartapps are tiny and relatively harmless subset of all that.
I'd rather think it is the other way around; there's lot less software in OpenRepos (or whatever equivalents exist) than for example in Debian main!
Whether the piece of SW is FOSS or closed source does not affect whether it is "a masterpiece of creation" however it might have an effect on whether it can be better;
You just cannot argue that it is easier to maintain closed source software.