I agree.
I do really like Nylas, it's mostly a pleasure to use.
But I'm using it with Gmail which costs me like $2pm for 100GB storage; the core (with I think 20GB?) is free (at the point of use, blah-blah advertising).
Is Nylas, the thing through which I access my free/almost-free email really adding $12pm value? I'm not so sure.