I have no idea what it is supposed to mean. grub2-bls became the default bootloader in Tumbleweed. It does not nuke anything. It simply neither supports the os-prober and the “traditional” grub.cfg nor (tries to) detect Windows EFI bootloader like systemd-boot does. Nothing stops you from selecting Windows in your BIOS boot menu.
Much more serious problem is that Windows creates relatively small ESP which will likely be insufficient to store all kernels and initrds from all snapshots.