It is not just compatibility. You cannot load them into the memory with your system dynamic loader. You need to also ship ld-linux.so with the new version of glibc you have, if you were to distribute your program independently.

On Windows you don't need to ship a new binary loader. I can just ship Windows 10 UCRT DLL (which is the new libc of Windows) to Vista and my binaries will work. The binary loader isn't interlinked with the libc.