Never once has the Linux boot manager/loader (either the original GRUB or rEFInd) been broken, by a Windows update or otherwise.
Windows of course has been well documented to happily overwrite any MBR bootloaders when you install it, but even that doesn't happen in a UEFI environment. Windows, rEFInd, GRUB, and whatever else you may have installed all have their own folders. It might change the default, but restoring your own choice is literally a matter of copying a single file.
EFI has plenty of problems of its own, but this is one it solved pretty well.
I've had it nuke my bootloader a few times when I used to sill dualboot (now full Linux).
One time the windows installer confused the encrypted LVM disk with a corrupted NTFS partition (because it had an NTFS partition on it at some point and underlying data wasn't wiped properly) and tried to fix it. Suffice to say, that required a back restore, so now all my encrypted disks have a 100MiB NTFS buffer partition for Windows repair to fuck around it (until I removed dualboot, I occassionally found remnants of an attempted repair in them)
The workaround for me was the "boot from file" boot option, where I would be able to walk the directories in the efi partition and start grub. Once this was done, it was back in the boot option list.