Rebuilding Lightmaps changes the level asset

Actually that is nod a bug, but a feature I know. But it is quite annoying.
Epics, maybe you can do something to this?
Now lightmaps are built to separate file *_BuildData.asset. And that is great feature. Thank you very much for it. They are quite big and we are not storing them in git repository. So every developer rebuilds lightmaps on their own machine, as they are purely cosmetic, at least for programmers and game designers.

But rebuilding Lightmaps changes level file every time you do this. Is there really any reason to change maps? That behavior pollutes repository with unneeded file changes. Can that be avoided somehow?

PS: Also one small wish - maybe you can split Level Blueprints to separate data asset too? )