Yeah, but deciding not to do so after hearing the specific advice is not necessarily a sign of being a head-in-the-ground ass. Especially if it’s just a video game recommendation.

Also, is the person making a recommendation based on what they know of my tastes, or because they want to gush about something they enjoy? I’m happy to hear the latter, but it doesn’t necessarily mean I will like it. If you love spicy food, I’ll gladly listen to you talk about it, but I’m going to ignore your recommendation to try it because I know things about myself, one of which is “I have no spice tolerance”.

Yes it is. Evidence is against you on this point when we're talking about population level behaviours, individuals vary of course which includes you

Not that experienced people are less able to consider other opinions, simply that when we're younger we depend more on volatile social acceptance metrics combined with having had less time to firmly establish our own preferences.