Plasma wayland has an automatic mode which should at least turn off VRR during desktop usage, as long as the application window isn't fullscreen. A hacky way that can help when VRR is active is to increase the minimum frequency and kick into LFC more readily, by creating a custom EDID (you can also do a sysfs edit historically but I think that's AMD only).
That's only really viable if you have a high refresh rate monitor with a large range. I've found that 120hz may not be enough (since you may end up with gaps where VRR doesn't work if the range is too narrow), which is of course the most common OLED TV refresh rate. In my experience a minimum of >=54hz minimises the flicker, but that may vary with the display.
There's also an issue with cursors where moving the mouse can make the refresh jump to the maximum. It only affects desktop usage and some games (RTS and the like, not usually FPS camera usage). There are fixes coming for this with Plasma I believe, but I'm not sure about Gnome. Forcing a software cursor may help, as others have indicated.
Vulkan mailbox mode is pretty much this and doesn't require game support (can be forced on with environment variables if it's not already being used). And since almost everything is Vulkan on Linux these days, one way or another, that covers most games (might be compatibility issues in rare cases).