Maybe it's the way I use it, but iTerm2 crashes (or hangs) fairly regularly for me on macOS. I usually need to restart it at least once a week, which means losing ~dozens of tabs with context in them.
I use urxvt on Linux, and I don't have any problems with it.
Edit: I should also mention that I see plenty of non-crashing, non-hanging bugs with iTerm2 that look like memory misuse to me: split-workspace mode (tiled with a text editor) causes wonky graphical errors, and I've seen what looked like buffer reuse artifacts when switching between monitors.
I have run across one - of maybe a dozen terminals I've tested because I'm difficult and have very specific requirements of a terminal - that crashes on weird input. I can't even remember which one it was, because I moved on, but odds are it was while testing unusual features like Sixel or ReGIS support.
It's been a while, but gnome-terminal on earlier gnome 3 releases used to segfault very frequently for me. It's the thing that finally made me seek out other terminal emulators