Preface: I'm not against F2P. There are situations and cases for both.
Why is there so much support for F2P like it's the next greatest thing ever?
Certainly there have been a large glut of derivative MMOs that should never have launched with a subscription when they couldn't support regular content updates, nor had the polish in the game to warrant players attention. But on the flipside of that -- my perception of 99% of F2P MMOs has not been a good one. They're either designed to sabotage gameplay to push for item store sales, or are generally of rather sparse features, low quality, and highly derivative in nature. Or they're failed sub MMOs that get retooled to increase revenues.
IMHO the best F2P ones I've found on rare occasion, are the ones that offer a "sub fee" that basically eliminates all the bad stuff about F2P. Unfortunately they still tend to be slower in content releases than regular MMOs. Like, one of my favorite F2Ps was Mabinogi. I probably spent about $20-25/mo on that. $15 got you the "premium status" which was basically a monthly sub that removed all the annoying time sinks tied to F2P. And then I paid for a rebirth of my character every 3 weeks to level faster.
I would much rather just pay a monthly fee and know I'm getting the whole game and not have to worry about where I'm being nickel and dimed at. I think the issue still is just that WoW was so dominant and had such polish, that people saw anything else with a sub as not nearly stacking up to the level of features it offered. With the decline of WoW over the next several years, we may finally see other games able to make their way with subs, or at least a hybrid system of offering both right off the bat in a sensible manner that doesn't seed misery into the gameplay without it.