They only get feedback from the people who do the surverys. The surveys are representative of their most engaged customers by their very nature. It's a slow process, but what the most engaged customer wants and what the average customer wants are not always the same thing, and there's the potential for that to diverge over time.I think the ayse they have set up is pretty good at preventing thst cul de sac phenomenon that killed 3E, 3.5, 4E, and Essentials. And precisely through thst measured conservative testing regimen and iterative products.
There's also this bizarre thing they are doing where they are presenting bits of an idea and then pulling back if they are not immediately popular. Some ideas need to be presented as whole packages. It's not surprising that people didn't like the cross class subclasses as they were made. The game as it is wasn't designed for them. But if the revised edition was designed more tightly (which they ought to be able to do now with a game that's over half a decade old) then they would probably work well - a lot better than basically shunting the idea off into feats. (Feats as they exist now have their own problems, the ASI system has it's own design constraints)