Differing priorities. Edge is based on blink now anyway , so as a core browser engine they’re roughly the same. It’s the higher level UX that is differentiated.

Safari has largely caught up now for web standards and mostly only lags behind in experimental features that are largely driven by Google anyway. But Safari has better battery use and privacy.

Chrome is good because Google see it as their play at a web OS. That’s why they shove everything and the kitchen sink into it.

So it’s just different priorities and the resulting differentiators. I don’t think any major browser is actually significantly better anymore today.