How to recover access to my old Linux distro after wiping the EFI boot partition?

I always keep backups of my EFI partitions just in case! I have my different Linux installations isolated—Linux #1 on SSD 1 has its own EFI partition, and Linux #2 on SSD 2 has its own too. It helps avoid issues during new installs. You might want to think about setting it up this way if you're transitioning from Windows to Linux and planning additional installations.

Just to clarify, wiping the EFI partition isn't mandatory unless you choose to do so. If you're careful, you can install the new distro without affecting it. If you do run into issues, instead of using external tools like Boot Repair, you could just use a chroot shell from your working distro, which most installers provide. You might also consider saving your current EFI files in a separate location before the new install to easily restore them later. And remember, having two different bootloaders isn't always necessary if that's something you're looking to manage effectively.

If you're looking to clear the disk, you can easily do that with gdisk using the expert menu to zap, but be cautious because that will erase everything. Make sure you know what you're doing! However, I can’t see how this information fits your question about the EFI partition.