I was going to give my son a system, with brand new Solid Steel rack but he has AirPods???

I can be considered an “old” millennial.  I like and enjoy hi end audio.  You didn’t go wrong, but I believe he didn’t go right.

I’m exposing my kids early... in hopes that they will latch on.  My 6yo keeps asking, where’s the record player?

Also trying to figure out what to give my (grown-up) kids. For sure it’s gotta be active and app-controlled. No cables. The Naim mu-so been appreciated so far, but want to find something more capable. The new active Buchard system maybe. Welcome to the future. Old hifi with all it's curious tweeks is dying.

I don't know; when I was growing up I'd likely be found in my bedroom listening through my (craopy) David Clark headphones (eventually replaced by Koss, which really weren't that much better), if not my Rectilinear XI speakers driven by Sony TC230 R2R with internal amp.  My step daughter (14 years older than my twins) got into vinyl and received my hand-me-down Rega Planar 2 (later Planar 3) and Maggie SMGa's; I don't think my twins could care less one way or the other (although they've benefitted from great sounding systems at home their entire lives).  Different era; different priorities.

What, did I take a wrong turn and end up in the "Ask Amy" blog? :)
No, it's the age-old situation of buying something for someone that they didn't want, which usually means you 1.) didn't pay enough attention to their preferences and/or 2.) you're trying to "improve" them by forcing your ideals upon them.  Example: "I bought you this book on how to organize your life - I think it might do you good".  My suggestion is to get rid of anything you have that you've offered to him that he didn't want, because if you keep those things around you will only be reminded every time you see them that he "rejected" your gift.  People do change, but they need to get there on their own.  I've tried to get my daughter to listen to my system to see how much better it sounds than her cheap Apple earbuds (actually bought her some Tin Hifi IEM's to get closer to better sound) and she'll listen the appropriate amount of time to not hurt my feelings, but it's clear she's not interested.

I went through this with two of my kids about a decade ago.  As they got their own places I showed up with good used equipment that I had carefully shopped for, or in some cases handed down.  After setting everything up they both dismantled it and gave it away or threw it out.  Ironically one of them did want something better recently for their TV and Video gaming so they took an AVR off my hands and I happily replaced it with an Anthem AVR with ARC.  Different Generation, Different Priorities