Not a clue. ROTR is better in almost anything but graphics, characters and plot. But what matters to me is gameplay, and ROTR has the better gameplay imo. It combines platforming, puzzle-solving, exploration, RPG elements and good gunplay, and it's all masterfully done. I actually think it's one of the best games ever made, so it's not a contest for me. I love U4, by the way, but it's just not the same. Both are ooutstanding games. But ROTR has better gameplay value, and more replayability. I feel like people enjoy more the fast-paced U4, but I enjoy taking my time to chill and exploring the environment, which is more compeling and interesting in ROTR. I still don't know what was the need about those big environments in U4, since there's nothing to do tbh.
I'd love that Crystal Dynamics made a "tomb" based Tomb raider though. More focused on puzzle-solving like ROTR tombs.