Well, I was not sold on FATEs too first. Heard they ruin community, like the Dungeon finder of WoW, or WoW itself. That they are the devil an should be avoided.
Fair enough, I did some Fates here and there... was nice, easy, fun to a degree. I do play a DD, meaning I tend to wait 30-80 Minutes for an invite to a Dungeon group. So lets look at it from the Math point of view. I can spend about 60 minutes waiting for a group, then spend another 40 playing that dungeon and get like 1/5 of a level and possibly some equipment.
Alternative rout, I go to an area of my level, ask for a FATE group and get an invite, play for 100 minutes and have like 0,7-1 levels in that time. Yeah I stopped doing dungeons, since honestly, waiting and shouting for members is not what I consider fun.

FATEs are not the problem. They are just easier to access and give a better reward/time ratio.