Make a homelab and setup local DNS. It's not that complicated if you don't want to get fancy. You can also team it up with DHCP using tools like dnsmasq which is lightweight and works on everything from raspberry pis and routers with flashed firmware to a whole computer or VM on a larger host.
You can do it. You should do it. Why haven't you done it yet?
Not saying what I'm doing is right, but giving my NAS a static IP works on any device connected to the network. My router doesn't support manual DNS entries and I don't want to go through the trouble of flashing OpenWRT just to do something.
You can name off tools that make it easier all you want, but how is the average user supposed to know that? When I set up my NAS, I wanted it to be accessible from the same address no matter what. I knew (at the time) about static IPs and manual DNS entries. So I went to my router's configuration and it didn't support manual DNS entries. So I opted for a static IP, and it worked. Sure, it's a kludge and not future proof, but I don't care. That's the problem. The "solutions" only work if you both know about them and care enough to do it the right (instead of the easy) way
Because it is work, and then it will require administration. Which is more work. Computers are smart enough to handle this, why can't everything on a subnet just have (for example) zeroconf?
You can do it. You should do it. Why haven't you done it yet?