This is bad news for me. I am working on a simliar project (gaussian splatting + dynamic scene). Our method is different with the mentioned 4D gaussian splatting, but I am unsure shall I continue or not.
If you're interested in the process - or exploring your specific approach then why stop?
Coming out with a method second is much less likely to be rewarded by the community: not being rewarded for work completed is not sunk cost, its just a straight up loss.
The additional interest might actually be helpful.