This is true.

To be fair, if you use only the Linux syscall interface, then a program that you compiled on x86 in the 90s will probably still run anywhere today. Linus is adamant about this.

But if you want to use... anything else, then it's unlikely to work at all unless you are very specific about your target. There isn't one company deciding that glibc or mesa or whatever is binary backward compatible on every kernel for every platform forever. Microsoft is, somewhat, one such company. That's why System32\*.dll have such stable interfaces -- it's their job to translate whatever late 90s system/graphics facilities some boomer dreamed up into whatever the current Windows hodgepodge of system services support. It's no wonder Microsoft is trying to drop support for hardware like crazy.

This implicit compatibility isn't true for all Windows programs, though. Consider Visual Studio. Couldn't compile my console program on my computer and run it on my dad's computer. He had to first install the "Redistributable," which for him and most people might as well be a rootkit and a super scary virus program bad guy.