The problem wasn't Metro apps per se. I think most people are enlightened enough to know that everyone is different. And if you like Metro apps more than desktop apps, then good for you.
The problem was how Microsoft shoved Metro down the throats of everyone who didn't like Metro apps. Win 8 booted to it. Hitting the Windows key took you to it. When they "gave in" and put back a Start-like button, all it did was take you to Metro. If you like Metro, you probably want those of us who dislike it to respect your choice. Well, those of us who dislike it and wanted the old desktop got no such respect.
It took me a couple months to figure out what was really going on. Microsoft was jealous of Apple and its App Store in iOS. 30% of the revenue for every iOS app sold goes to Apple because the App Store is the only way to buy iOS programs. That had Microsoft's bean counters absolutely drooling. Imagine if they could get a 30% cut of every Windows program sold! They'd make a fortune! Well, they already make a fortune, but they'd make an even bigger fortune!
Thus was born Metro and the Store. Metro was going to be the "new" type of Windows app replacing the old desktop apps, and (here's the crucial part) Microsoft got 30% of every app sold in the Store, and the Store was the only way to buy Metro apps. Then they did everything in their power to force people to use Metro. The OS booted to it. The Windows key took you to it. The Start menu took you to it. The search function was through it. The list of installed programs was accessed through it. Certain settings and customization options are only available through it. They basically took a dump on all of us users who preferred desktop apps, in hopes of trying to get a 30% cut of every Windows program sold.
Once I realized that, even if I liked Metro, there was no way I was ever buying a Metro app. I use Windows and Android specifically so I don't support those market capture tactics used by Apple. I will not help that business model spread. It's a shame because Win 8 has a lot of nice improvements. But I have to install a bunch of 3rd party customization programs to make it behave as if Metro (mostly) didn't exist.