To my knowledge Comic Sans predates all of the dyslexia specific fonts. It's liked in the dyslexia space because all of the letter forms are quite distinct and therefore easily differentiable.

It existed before dyslexia specific fonts existed and there was a dedicated effort to create them.

It became popular early on for dyslexia because it just happened to be really useful for dealing with the issue.

Compared to a specific font designed for dyslexic people it doesn't hold a candle to it. But that doesn't make it bad for the job either there's a reason it got popular for that usage in the first place.

For like a good 10 years it was basically the only good option. Nowadays there are just much better ones and anyone still using comic sans I would hope it's just using it for silly things.