Milestone birthday and anniversary celebrations/gifts I have done for DH with great success include:
- Big trip to significant location
- Special dining at a favorite restaurant, private room or buyout
- Vintage watch from relevant significant year
- Vintage alcohol from relevant significant year
- Rug/textile/art from relevant significant year
- Antique with some sentimental significance (place/function)
- Art that is his taste (not mine or shared) for a space that is primarily or solely his (office/home office)
- MTO shirts/suit w cufflinks nodded to our wedding cufflinks (fwiw he is in tech and *never* wears suits, which made this a very popular gift -- my DH at least values gifts with sentimental rather than utilitarian importance)
I think all of the other suggestions are lovely gifts, but in my family would be considered regular bd gifts and DH, who is very sentimental, would be hurt if a milestone gift was something "regular" or useful like even the nicest pair of shoes, wallet, or belt and didn't have some sort of attachment or nod to the milestone itself. I liked someone's suggestion of a standing desk. I got humanscale adjustable stand/sit desks and herman miller chairs for each of DH's home offices for one significant but not milestone BD, but knowing his sentimental side also got him sets of Happy Socks w a theme that referenced his childhood. He uses the office setups more (especially now BC covid), but loved the socks the most