Complicated. Everyone gets to have opinions and some of those opinions are going to offend people. It's arguably inevitable. The social consequences of having opinions of one kind or another is a pretty standard facet of being human. And validity is non-trivial to define. People have their experiences and they are valid to them but that won't excuse them from the consequences of having an opinion that is shitty (e.g. "Nazis weren't that bad" is an opinion that some people honestly hold and also merits a punch in the nose). So my shitty not really answer is "sort of?".

One caveat (arguably unrelated) is that a lot of people like to state wrong things as opinions (e.g "I think the earth is flat") and will claim that you can't refute them because "that's just my opinion". It's not, it's an objective fact. Those aren't valid.

Side note: I feel like you're trying to lead me to something and I approve of your style even though I feel like I'm about to be wrong about something.