I'm definitely feeling that way these days.
When I first started learning Android, I was very excited about the resource system. The ecosystem is highly fragmented, but they give you the tools to deal with it!, I thought. How cool, I want to learn from their wisdom!
Six months later, I'm actively shopping for a different UI framework. This one makes easy things hard and hard things impossible. I was recently trying to make a button 40% of the screen width and aligned kinda leftish and kept from getting too big on wide screens. In CSS, that's couple lines, maybe thirty seconds. But in Android . . . well, I spent six hours thrashing through documentation and recommendations and opinions on StackOverflow before I gave up and wrote my own Button class.
It's really that bad.
Ever try to change the color of a button on Android? It requires something like fifteen 9-patch PNGs, two or three arcane XML files, and navigating a style hierarchy for your activities. No siree, no .myButton { border: 3 px solid #C88; } here.
Ever try to wrap text on a canvas? Or scale a font based on the display size? Or add an element to a view when a screen is a little bit larger? The hoops you have to jump through are simply amazing.
I'm convinced it's not fragmentation, per se, that's the problem. The web has even more fragmentation, and it handles it well enough. No, it's that the tools you're given for dealing with the fragmentation are so very poor.