For me at least it looks like the new patched version is a route breaker and from other comments I've read it isn't kind to user created content either. I have two installs of TS2019 on my computer and after seeing what the patch did to one of them I'm certainly not going to patch the other TS2019 installation with all my custom made assets installed on it.
Need to download the missing items from the DLS, they are all there, at the correct build, presumably this is due to items being included as payware that should not have been for whatever reason, apart from that, zero problems on either of my two TRS19 installs.
We know why as it was to correct the issue with payware that should not have been. A bit more of an explanation as to what was being done and any action we needed to take would have stopped people assuming it was breaking anything as it appears certain items have been removed from DLC as never should have been included, some pofig v6 trees are now only on the DLS so need downloading for a couple of the DLC routes and here one of mine.
Here I have 3762 assets I created myself installed not one item has been affected.