On top of the current temporary situation of not having access to things that were carried over to 2024, there seems to be a selection of things that were not carried over to 2024 at all.
For instance JustSim EDDV is entirely missing, it’s not even in the list, not even disabled. See: JustSim EDDV purchase in Marketplace not showing in MSFS 2024
If I had bought it via an external shop I could try using it and maybe live with some glitches, but the airport has not been added to my 2024 list at all.
Same for FSDT LFSB for instance, but there I got the info that the developer intentionally disabled it for 2024 until a compatibility fix can be provided to the Marketplace (for free). Meanwhile anyone who bought the airport outside the Marketplace can not only use it but also already got the compatibility update.
It’s just a mess and the worst thing is you don’t know the status as to why some things are missing and when they may or may not be added, you’re just out of luck if things are missing.