What happens but can never be observed, may aswell never happen from the p.o.v. of the observer. It has no consequences to say it does, or does not, happen (for if it did, those consequences would make it observable).

No, it isn't. The fact that a particular observer cannot detect an event does not in any way justify the claim that that event never happens.

> may aswell never happen from the p.o.v. of the observer

Whether or not an event "happens" is not a matter of any particular observer's point of view. At least, not in General Relativity. In GR, an event happening means there is a point in spacetime at which it happens. That point is either there in spacetime or it isn't, independent of what any observer can or cannot detect.

You can say an event has no causal effect on a particular observer, but that's not the same as saying the event never happens.