I still play SimCity 2013 today, and despite its flaws, I much prefer it over Cities Skylines. SimCity feels alive, with a great soundtrack, good looking visuals even today, and I love the futuristic expansion pack.

Skylines feels less like a game I want to play in my free time and more like a city planner tool. The graphics style also somehow feels much colder and more outdated in comparison.

I honestly think SimCity 6 with bigger cities and updated graphics would be a massive hit without changing much else - the multiplayer aspect of sharing resources, contributing to pollution, workers and students, etc is really unique and should be kept.