This is about non-mutants, not humanity. Right now Kamala Kahn can't go to Krakoa because she's not a mutant.
Again, it's a nation not a social club.
So does Apocalypse and Selene. This discussion isn't questioning Krakoa's right to exist, its about whether it rejecting non-mutants from going there for tourism and immigration is morally right.
The "health care" for mutants in Krakoa is immortality, and resurrection! The rest of humanity don't have permission from Marvel editorial for their scientists to impact their own nations positively with things like this.
Grenada has a population of 112,535. They can't resurrect people, they don't have super-powers, and they're not resurrecting millions of people from another country to claim as there own based on the genes yet they still let foreigners from numerous countries into their space. Also, their land won't grow unlike Krakoa.
https://tourismanalytics.com/grenada.html
You forgot about the deals wth the very human cartels, Selene trying to take over the American government with Norman Osborn, Sinister having his own Suicide Squad, Apocalypse starting a war with Avalon and putting a dangerous reality warper puppet king at the top, and whatever X-Force did to a rival country.
Krakao employ human scientists but won't let them have rights on their own country.
Krakoa's a First World super power, though it's borders are like a sieve that a bunch of old ladies can get in without a sweat.
https://abload.de/img/15a3j17.jpg
Ferro, mutants are at their height at the moment at being a global force, whats worrying is that they're tainting all their good works with horrible governing.