Welcome to the site, Rick,
I'll second 2017's message...
All players will face big hurdles on a regular basis, particularly if their goal is college ball and/or beyond. The goal should be "leave no doubt". Work to be so much better than the next guy, there will be no doubt who should be playing... not in the parent's mind but in the coach's mind.
And, yes, results of one AB or even good stats over a season of JV may have no bearing on his standing in regards to V and certainly no bearing in regards to college. Consider the possibility that "parents in the stands" comments may have been common courtesy (what else are they gonna say?) or reference to the thought that it doesn't make sense for anyone on JV to not play, regardless of abilities, unless there are other issues.
I don't know your son but i suspect there may be a disconnect between your perception of his abilities and actual. It doesn't add up that a JV player who is not getting steady PT, even with the worst of political scenarios, would be looking to be picked up by one of the strongest travel programs in the country. So, besides continuing to work hard to be the best he can be and leaving no doubt, I suggest getting a neutral opinion from someone qualified to assess his abilities, strengths and weaknesses and advise (not a current coach or instructor - they have motivating factors to be less critical.) Ask that evaluator to lean toward the side of overly critical. Then, find a suitable travel program and good instruction. And work your butt off. Not once in a while. Commit.
I am a HS coach and I have several kids who are sort of in the same boat, languishing as tweeners. Some totally take the bull by the horns and change their destiny, some make modest efforts to change, some are just there to be with the guys and some "are being terribly wronged by politics" or have some other "reason" they are not in a better position with the team/program. Which will he be?
BTW, I have a few of those guys this year that really committed between 10th and 11th grade and the results are really amazing and inspiring. They will still have to battle for the PT they desire but they have thrust themselves into the equation.