That’s crazy that coach said that to your son. Lots of kids are quitting at this age. Yes, the GK is a bit on the heavier side right now and the team was becoming more competitive. I’ll never know if it is healthier for him to keep playing or to stop. At this age, it can still be hard to tell if kids are playing because they want to or if they feel pressure from their parents. It just saddens me to see a kid seem so down. Sometimes I’ve seen him show up to practice with tears in his eyes.Unfortunately 12-13 is the age where: a) those GKers that are not physically fit (if they are playing at higher levels) begin to stop being effective...if he's heavy and out of shape and your team is advancing in the ranks, he was going to quit anyways because he won't be effective at all since he won't be able to extension dive and will be too slow to sweep and 1v1; b) for those GKers that struggle with confidence, it's the age (according to my son's GK coach) where he usually sees them quit...it's no longer worth it to them if they don't think they can play college, the pressure is too darn much, and it's no longer fun....if they don't find a mentor it's hard for them to survive the pressure without cracking; c) the not too many shots in the game thing also isn't great (for him)...it means he isn't busy particularly if you guys aren't playing from the back and he isn't using his feet (he may be just praying he doesn't have to do anything in a game)...and when you guys face higher level or stronger competition, he won't be ready for it....GKing is like the Goldilocks of soccer...you don't want too many shots, you don't want too few, you want them just right.
Small story: When my son was U10 he was on a team he didn't get any shots on and the team was routinely winning 10-0, 9-0, 8-1...think the closest score was 6-2. He thought he was doing awesome. They then advanced up the ranks in league and state cup and all of a sudden he's giving up goals. He's confidence gets really shaken. Plus, the coach's expectation was just through the roof on stuff he had never seen in game before. Coach afterwards told him he had no business whatsoever being a goalkeeper. That shattered him. If he hadn't had a strong mentor, and he didn't love the position that much he would have hung it up right then and there and he almost did
Over the years, I’ve encountered several parents who would get so upset if their kid was put in goal. My own kid is short and a string bean right now, mostly center mid. He loves to fool around and go in goal during free play. My youngest wanted to try soccer at 7. I take him to practices for a few months. This was early on in the pandemic so games had not started. Coach has him practicing a lot in goal. I thought he was pretty good too. Wow I thought to myself that the coach won’t have to deal with a disgruntled parent. Unfortunately my kid quit and his scatter brain has already moved on to other things.