It’s a fair remark here, and specifically in the case of 32-bit x86, it’s not really as much of an issue. It breaks down on ARM architectures mainly, and probably will also have the same issue with MIPS and RISC-V (though neither are supported in snapd today).
At least specifically with 32-bit x86, Debian did baseline i386 until recently. OpenSUSE and Mageia do i586 (meaning certain instructions aren’t used), and Fedora does i686. There are CPU incompatibilities for this, but in practice I don’t think we’ll encounter them much except with IoT and specialized computers like the OLPC XO laptops.