It's like an RGB light or RGB strip that you normally stick behind your TV or off to the side, and it can "react" to whatever's on your TV, so that the colours of what's on screen kind of "bleed" out to your surroundings.
I have a Govee myself that I bought completely on a whim. While I do agree it's particularly good for animations (Akira is another good one), there is a split second lag as the camera or whatever "reads" what's on screen and then reacts, which is a bit offputting. The novelty wore off for me pretty quick and I haven't used mine in literally like a year...
No issue with lag here, and I use it regularly
Which version do you have? As I have Govee T3 Lite and firmware updated