Windoze often causes breakages when multi-booting with other OS's. Windoze is well known for nuking other OS's, so this is hardly unique to Garuda. Any time you multi-boot you should expect boot breakages as a natural consequence. If you don't want to experience that, then don't multi-boot.
That is exactly why I have not multi booted in over 15 years. Each OS really needs to be on a separate hard drive if you don't want to experience these kinds of issues. The same advice goes for installing multiple desktops on the same Garuda install. Sure it can be done, but if you don't know what your doing your only asking for problems.
An internal snapshot is not a legitimate replacement for a for proper external backup strategy. Snapshots are very handy, but like any prophylactic measure they have been known to fail.
Any backup system that backs up to the same drive as the source is not a reliable backup system. System snapshots are a handy adjunct to proper backups, but they can not be considered a valid backup method. Backing up your system is your own responsibility, not the distro's.
It is unfortunate you suffered a system breakage, but when all is said and done the user must take responsibility for protecting their own systems data.
I use a hot swap dock with three 120 GB SSD's I alternate as my boot drives. I simply use dd to image one drive to another, then again to the third drive. That way I have two redundant backups at all times. If I suffer a breakage I simply shut down, swap boot drives and restart. I don't even have to perform a system restore and I'm back up and running in under a minute.
That is the beauty of having a proper backup strategy in place. There is never any worries about downtime or lengthy troubleshooting to repair your system. If you want that kind of peace of mind then you must implement a proper backup strategy for yourself.
If you want to run a rolling system there will inevitably at some point be breakages. That is simply the nature of the beast. Now that Windoze has switched to rolling system updates, I hear they are prone to breakages as well.
In the end you need to learn to manage your own system. Do not multi-boot if you,do not have the skills to manage the inevitable breakages that are certain to occur if you insist on Multi-booting. Garuda did not install more than one OS on your system, that was your choice. Instead of railing at Garuda you need to look in the mirror. Perhaps then you will realize it was the decisions you made that caused this predicament (not Garuda).
Welcome to the forum, but starting off your inaugural post with a rant isn't exactly the best introduction (or the best way to get assistance).