Hey Joe,
I just noticed a couple days ago that ZorinOS 18.1 has released with the kernel updated to the 6.17 kernel from September last year.
Possibly cognitive bias on my part, but I'm finding ZorinOS 18.1 subjectively very, VERY snappy and responsive.
If you find yourself sitting around, twiddling your thumbs, I'd be interested in knowing whether the update resolves your previous stuttering issue. 
I appreciate that not everyone has the time and pain tolerance to tinker to the degree that I do. 
Speaking of which, I'm now running CachyOS's stable release of Linux Kernel 7.01 featuring fully supported NTSync.
After all gaming performance testing I went through, I'm having mixed feelings about whether I prefer my game with NTSync on or off. I need to test the trade offs.
But like I said, I like to tinker.
I think Zorin consciously keeps a year behind kernel releases to assure stability and time for community kernel modules and drivers to fully integrate kernel changes.
If you still have ZorinOS 18 installed, I highly recommend trying out the 18.1 update. It's delightfully snappy and refined.
In other news, the Zorin community has started playing with the latest version of Gnome.
Hat tip to the forum moderators for actively keeping this community alive and interesting.