Not if it has all the essential features, it has no 3rd party ads, tracking and is a privacy focused mail client.
I only bought i because i could test it for months and saw everything works and it being updated and well maintained, it's kinda pricey for a mail client.
There are for sure nagging experiences in other programs, Fairmail is not one of them.
They don't care about that, they want to move their consoles, that's why they're completely exclusive.
Chances are you don't have every other platform and buy games for your Nintendo console.
Anybody can hate on them, but they know business.