Add-ons are always a thorny problem, as X-Plane have found. When they recently updated the main core of the sim, many add-ons caused crashes. Although they got much of the blame, this was not the fault of X-Plane itself, but many third party developers had not strictly followed the rules laid down by Laminar Research. Although this did not cause a problem on previous releases, it was disastrous on the X-Plane upgrade to Vulkan. It caused customers lots of problems trying to find out which add-on (or add-ons) was the cuprit on their particular system, and then of course a time-delay waiting for the third-party developers to patch their add-ons.
I don’t know if MS are worried about a similar problem on FS2020, but I certainly would be in their position. So hopefully they are checking, not just that the add-ons work, but that they are not likely to cause crashes in future upgrades to the sim. Relying on customers to work this out for themselves is obviously a nonsense.