Here’s a PBS video that explains things like facts, theories and hypotheses:
I won’t dispute that many people can conclude that they are experiencing the same feeling, and they may even believe the cause of the feelings are also the same, but it isn’t a fact — it is at best a shared, non-rational hypothesis without testing.
Someone saying they feel something doesn’t in itself legitimize it to anyone else.
If someone says “I feel this way because….” and yet there is very little or objective evidence to show that the ‘because’ is true beyond the feeling itself, then it is just that — a non-rational hypothesis without supportive testing.
Seemingly shared feelings among populations are testable, and they shape societies and their morality. But even those societies can understand and accept that it is irrational, and at least attempt to base their understanding on a scientific measure and agreed upon terminology.
I agree that humans are terribly complex. But that complexity, and saying “you can’t possibly understand my experience, so you’ll just have to treat whatever I have to say I am feeling as relevant to you” doesn’t validate whatever it is.