Limitations often breed art. Compare what George Lucas did when he was on a shoe-string budget to what he did when money was no object... frequently directly to what he made when he was on a budget. Pixel art is appreciated by people because they can see the limitation and appreciate how the artist worked around it. However, restricting yourself to pixel art does mean adopting a limitation voluntarily when you probably also have a lot of other ones to deal with too. Sometimes one more limitation is one limitation too many.
Pixel art is very trendy right now, but it probably won't remain so forever. Shooting film in black and white used to be all that was possible. Then it became what was cheap. Today, we still see some B&W films for aesthetic reasons, but it's very uncommon. Pixel art will probably become very similar to B&W film eventually. Seldom used, but used for a specific effect when it is used.
There's room for plenty of aesthetics besides pixel art and "HD" though. With modern displays, there's no reason that games can't borrow aesthetics from other mediums. Watercolors, comic book print, you name it. Heck, even though it's similar to pixels, I'd kill to see a good game created to look like a Byzantine mosaic! Adopting these limitations when appropriate offers artists a chance to take on problems nobody has seen handled before, and it's therefore more interesting than just working with the same artificial limitation everyone else is currently working with.
I'd just like to expand on the idea of a mosaic aesthetic a little bit more. It may seem like mosaics are just irregularly shaped pixels, but it's actually much more than that. Mosaics were made out of a variety of materials that scattered and reflected light in very different ways. Some tiles were matte, some colored glass, and others backed in gold leaf to amp up their reflectivity. Mosaic tiles were also angled to reflect light very strategically, allowing the artist to make some features grab your eye. A mosaic-based game would require a virtual mosaic toolset that would give artists the ability to simulate different tile materials and angles and a lighting engine to render the results. The resulting image would have complexity on a much smaller scale than a single tile.
Pixel art is very trendy right now, but it probably won't remain so forever. Shooting film in black and white used to be all that was possible. Then it became what was cheap. Today, we still see some B&W films for aesthetic reasons, but it's very uncommon. Pixel art will probably become very similar to B&W film eventually. Seldom used, but used for a specific effect when it is used.
There's room for plenty of aesthetics besides pixel art and "HD" though. With modern displays, there's no reason that games can't borrow aesthetics from other mediums. Watercolors, comic book print, you name it. Heck, even though it's similar to pixels, I'd kill to see a good game created to look like a Byzantine mosaic! Adopting these limitations when appropriate offers artists a chance to take on problems nobody has seen handled before, and it's therefore more interesting than just working with the same artificial limitation everyone else is currently working with.
I'd just like to expand on the idea of a mosaic aesthetic a little bit more. It may seem like mosaics are just irregularly shaped pixels, but it's actually much more than that. Mosaics were made out of a variety of materials that scattered and reflected light in very different ways. Some tiles were matte, some colored glass, and others backed in gold leaf to amp up their reflectivity. Mosaic tiles were also angled to reflect light very strategically, allowing the artist to make some features grab your eye. A mosaic-based game would require a virtual mosaic toolset that would give artists the ability to simulate different tile materials and angles and a lighting engine to render the results. The resulting image would have complexity on a much smaller scale than a single tile.