Nothing from Adobe. Affinity Designer is a competitor, but it's hobbled by some bad UI, missing functionality, and a "we're not gonna fix that" attitude from the publisher. Not a terrible option, but it has been disappointing.

There's also Sketch, which offers a more limited toolset than some and seems to target UI design. Not bad. Some unintuitive UI and some bugs here and there that aren't getting fixed, but you can get stuff done and it's supported by quite a few design-collaboration platforms online. There doesn't seem to be any official user forum for Sketch, though, which is annoying. Someone can correct me if I'm wrong on that.

Corel Draw, which is Windows-only, has always been better than Illustrator. It's pretty good.