Just a bit of a lesson in general. While you guys are probably doing the right thing by thanking the coach for any help and informing him of baseball plans - you don't go out seeking praises and pats on the back. Yes it is nice to be told good job and have people that are also excited for you, but that is what friends and family are for. Nothing wrong with letting the coach know, but don't go searching for validation. He will be receiving it in the form of interest and eventually offers.
That being said, most high school coaches are just teachers who played baseball. Not all were pro stars, college stars, or high school stars. In fact many don't know what they're doing all that well. I don't know the situation but there are plenty more teachers who coach than coaches who know their way around a recruiting trail.
Maybe he is waiting for more news other than "talking" to schools. If he doesn't follow up with you/your son next time he sees him I would just chalk it up to a grumpy old coach
"Most and "many?" Generalize much? Damn teachers who coach who don't know anything!
For the OP, I was also confused when you assert or at least suggest that the HC is coaching summer ball while not mentioning whether your son is playing during the summer for him. Coaches often have other responsibilities during the summer and so, if they get a chance to take off for a week with the family, they do. I know that for a very long time, I coached both Legion, and Junior Legion during the summer and didn't have much of a window to vacation with my family. Then, factor in that my daughter was playing all over the country and so, I never had much time for anything. I don't know your situation. I would have responded if I could.
Now, as a softball coach, I am actively working hard to get my girls in college and so, those parents are making sure to keep me up to date and I am constantly making contacts for them. This past senior group, I was 3 for 3. LOL