

There used to be significant differences in performance that drove browser choices. The top dog browser always had a way of getting fat and slow and then something else would come along. This is how Chrome got its start. But today’s much more powerful hardware hides a lot of poor performance, and most web bottlenecks are in the content (ads and shitty site design) where the browser can only make a small difference.
It’s an almost universal problem. Everything wants to grow so it starts doing things their existing users don’t like, because they’re trying to appeal to people they don’t already have.