I joined the fediverse when Reddit made their API changes.
For me, personally, I found Kbin/Mbin to be a sort of hybrid between Twitter and Reddit, and I wasn't a fan of the layout. Lemmy felt a lot more like the Reddit-like experience I was looking for.
However, PieFed then came along and it feels like Reddit, but has features that cater to the Fediverse much better than Lemmy does (such as being able to combine communities into feeds, crosspost handling,), as well as other features that are great (polls, spoiler blur for image posts, etc.).