Badly performing addons are the main reason behind Firefox crashes. The majority of users don't use addons. Of those who use addons, the vast majority use just one: an ad blocker. Those addons work fine under new Firefox.

There are lots of reasons to use Firefox over Chrome. It's not designed to drive traffic to a search engine. It has far better privacy out of the box. It's a standalone browser that isn't tied to the operating system for things like personal certificates. It doesn't lock its settings to the operating system so you lose all your passwords, extensions, and extension settings if you move it from one PC to another like Chrome does. Etc.