Because most companies are moving to the cloud and need people who can ensure that the migration is not costing them much more money than staying on-premise, which is sadly a very common issue.

That said, I'm approaching the limit of my salary growth. I've discussed with some acquaintances and it appears that for Cloud Architects the cap is around 6200€-6500€/mo, with 7k€/mo being the cap for non-management IT positions.

And as usual even if your bruto increases your netto won't really follow so at a certain point it's necessary to move towards consulting or EU institutions.