As usual, the first iteration of a particular form factor has some design compromises that consumers may or may not find acceptable. And it may have some kinks or flaws that will be sorted out in the next iteration. But if the future of premium smartphones is all about folding screens, then I think it is fair to say that Samsung are ahead of Apple in that respect.
It’s not true, of course, that nobody buys Android tablets. You seem to have forgotten about Amazon’s Fire tablets, which use a forked version of Android. But perhaps one of the main reasons that Android tablets in general haven’t sold well, is that people don’t like to switch between mobile devices — so perhaps a folding phone will solve that issue.
I think where Apple gets perfectly fairly criticised is when they hike up prices without sufficient new innovation to justify those hikes. That’s completely different from Samsung charging a high price for a genuinely major innovation.
And yes, Apple has bet on putting a lot of effort into getting their own ARM chips ahead of the competition and have had a lot of success. But it might possibly be that other technologies — such as bendy screen technology — turn out to be more critical than chips over the next few years. Time will tell! :)