I have several mobile devices (phones, tablets) and there is no (3D) game lagging on them.
Btw, check out the Lego games. Some of them are in 2D and some in 3D.
All with a very very good quality.
I also liked a lot Monument Valley (would be difficult to build in 2D I guess).
Personally, I love racing games with a perspective view like super Off-road or power-drive.
Those games were made in 2D and have this pixelArt charm, but I'm not sure that an editor would do such a game in 2D nowadays.
Also, to me, it looks like having a perspective view always gives a plus compared to flat graphics.
Ouais