Hello. I don't use Garuda, however I do use Arch and have tried out TKG kernel builds from Chaotic AUR. However, based on my own testing I have come to the conclusion that the BMQ scheduler for now at least has some issues that make it unviable to be the default kernel.
The first problem is with BMQ's deboosting mechanism. BMQ seems to deboost/boost tasks when they spawn dependent on their nice value. The problem with this is that it can result in hangs/stalling/freezing under high system load, which is what seems to happen. For example, if I run stress-ng and play a YT video, the YT video will completely freeze until I set the stress-ng process's nice value to be higher (lower priority) than the browser's process. And I think this is unacceptable because I have not needed to do that with the other alternative schedulers I have used (PDS, MuQSS, and CacULE specficially).
Worst of all, BMQ seems to have hanging issues with some games. People report Civilization 3 as one of the worst offenders and from my own testing Killing Floor 2 also seems to hang when loading a map with BMQ. Using any other scheduler, this behavior is not present.
And btw, you don't have to take my word for it. I've heard a lot of people in Discord servers and Reddit threads complaining about these problems. I have no idea if this is with the Arch kernel config or not (I didn't have these problems when compiling my own kernel with BMQ on Debian for example), but for these reasons I think the default kernel should be changed to either TKG-PDS perhaps, or maybe even TKG-CacULE/CFS (CFS has gotten a lot better in recent kernel versions, but it's still not up to snuff with low-core count CPUs, and PDS specifically has better frame times in some games).
The reason I am making this request is to lower the amount of potential threads about people saying a game is having poor performance/hanging, or the system freezes with high CPU load etc. In order to make a good Linux distribution for newbies, it needs to be stable and use stable components unlikely to have any weird interactions with specific programs/ anything within user land.