PoE has a bunch of timed events too, just without the actual timer. Works way better, but probably mostly because it can be rippy sometimes. To be clear, I'm talking about Ritual, new Harvest, and Azurite events. Wave-based systems can be easily seen as timed events, and they're boring as hell most of the time. But Rituals are actually kinda working for me. Last Epoch's system doesn't work for me. Anything D3 ever did doesn't work for me. Baal lead-up does work for people.

To sum up, it's obviously based on either difficulty or reward, but you almost always need to remove the actual timer. Time 'slows down' when you're just looking at a clock so that's kind of a design noob trap to have.