It's a problem with some tracks indeed. And yes, it will be present in some of the maps we're updating... if they used those objects.
However, authors can update their own maps to fix those issues (once the remapping is sorted out). Or if the author is inactive, someone else can report the map and we'll update it for them eventually.
Not all lightmaps will need to be converted again, just the ones with the issue with those objects. And even they are playable, but may just look a little bad until they can be updated.
It's an imperfect system, but we can't wait around to update every map until all the bugs are fixed, or there won't be many maps to play in the coming weeks/months.
And yes, lightmaps and objects aren't the only issues. Geometry changes to some blocks will affect some finely tuned jumps. For instance, I know one map by Voyager006 in Canyon that had a jump where you jumped over a fence. Now your car catches on it most of the time. Obviously most PFs will be broken, if they're not broken already.
The good news is, the vast majority of tracks will probably be just fine.