Overdone, but that doesn't mean I don't still like some of them. Like anything, it has become a trend and a lot of devs - especially indie devs - are piling on the retro bandwagon because it's the "in" thing to do. So it comes down to whether the game is truly a fun homage to retro games or just trying to mimic the style to make a quick buck with no real substance or originality to call its own.
Games like Shovel Knight, Scott Pilgrim, Rogue Legacy, and Mighty Switch Force (just to name a few) are all incredible games that merge the best of retro game design with enough modern ideas & conveniences to make them fun and very memorable. They also use the pixel art style to great effect, and are all truly gorgeous games in their own right.
Games that overdo the pixel effect - Slain comes to mind as one I tried to play recently - just come off as ugly & cheap looking to me. It feels like the dev used the style because they probably couldn't do any better. Maybe that's not true, but that's what it feels like to me.
As an example of a game that felt hollow to me, Cursed Castilla just came off as a clone of Ghosts & Goblins, not an homage. If it had released back in the day it would have been labeled a knock-off. It didn't feel like it brought anything new to that style of gameplay, rather it just rehashed what G&G had already done. There's no point in that IMO.
