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

Here's the deal you've a hobby, a sound system, maybe extra equipment. Your kid's probably grew up in your house and likely were exposed to hearing and all involved. The key word is they grew up, and developed their own way of thinking wants and needs, bingo you've done your job.
We can't expect the dumping of unwanted or unvalued junk on them to be accepted. Attempt the turn over if excepted fine if not there's always ebay...
Move on.

My daughter just started graduate school, and moved in with the Boyfriend.  I gave them a McIntosh RS100 for their new apartment.  They love it.  Can't wait to show up and hear it.  Obviously better than an Amazon Echo!  Plus, now they are a proud part of the McIntosh family without having to drop thousands of bucks!  It is a parents role to properly indoctrinate your children!

My son is in his early 40’s. He grew up listening to music on my various systems, mostly vinyl and CD. He was always interested in music as a kid and has been to many concerts. He was also in a band for a few years until marriage and kids took priority.

About 8 years ago, without any encouragement from me, he started buying used LP’s and playing them on a Crosley type record player.

A couple of years ago, I started upgrading my system and gave him a Rega P3-24, Harbeth C7es3’s and a Yamaha integrated. He is absolutely thrilled with the sound quality. Now, he even buys the occasional new LP.

Just recently, for his birthday, I gifted him a Node2i and a subscription to Qobuz.
It gives me immense pleasure to see him enjoy good quality audio.

Oh boy did I take a bit of lashing from some of you. I didn't say I was crying over it, I just wanted to share, discuss, and listen.
I come from a musical family, and my son plays a clarinet really really well. He loves music, I thought I had an opportunity to do something nice for him, which he always appreciates, and was surprised. When the family is all together (5 of us) we play cards, board games, and other stuff, and all 3 of my kids pull records off my shelves, clean them first, and put on what they want to hear. We must have had the TT spinning 5-6 hours a day during the previous hard months of COVID. Naturally, I thought this would be a great no reason present for my son who is going to school for Mechanical engineering, He loves the TT's and watches reviews on YouTube with me, and thinks it's a good looking rack. He actually picked the SS rack and put it together for me. I thought he would enjoy my gift. Some of these comments seem like I'm a jerk. I'm not.
If anyone can suggest the best place to sell the rack I would appreciate it. I got all kinds of scams from Craigslist when I sold the heavy bag I had in my basement, and who wants to pay shipping on something this heavy.

You did do something really nice for him. You tried and, believe me, your effort won’t go unnoticed or unappreciated......in his way and time; just like the way he chooses to listen to music....his way. Don’t beat yourself up over this and don’t attach undue significance to common generational differences that are not that important in the scheme of life. We’re talking about someTHING you value and not about a life VALUE.

Having had similar experiences with my sons, I can tell you that there is something for us aging audiophiles to learn from events like this. First, the quality of sound available to your son from his portable devices is infinitely better than what was available from portables when we were his age. We do get conditioned to listen to music a certain way and with a certain type of gear.  I suspect that had decent sound been available from portables back in the day, there would be fewer audiophiles (as we define the term) today. Perhaps unfortunate, but probably true. Along with that comes the reminder that it’s the music that matters most and as nice as audiophile sound is, it is not necessary to enjoy music in a meaningful way. Take your son to some quality live performances; that may really rock his boat.