It’s a matter of supply and demand.
Microsoft wants to earn money from the store with as little financial effort as possible. MS has been known for decades for comparably bad support of their own features and only improved a bit when they were forced by very strong competition. Internet Explorer has always been one of the worst internet browsers, so people went and got Firefox, Chrome and others. IE lost massive market share and so they were forced to work on it. Windows itself is another example what happens if you try to sell almost the same version over and over again so they had to change the business modell, the last win I purchased was 7 and from there I got 10 for free and am now offered an upgrade to Win11. Sure, there are other things happening in the background but for me as a user and customer it has improved. The win store is a big problem at the moment but who purchases stuff at the store when you get better or the same stuff somewhere else?
Why would I get flightsim addons at the ingame marketplace if there are so many so much better vendors all over the internet? Eventually MS will either have to improve their MP or they will lose market share, 3rd party stores won’t sleep for sure. As long as people go there and blindly run into the same issues for the third time there is no need for MS to do anything. It’s all about our consumer behaviour. As long as “you” purchase lowest quality helicopter addons they will release every week. It has to pay out, otherwise neither the dev nor MSFS would release them.
The Marketplace is a business that pays out. They will not change their offers just because a handfull of people complain on a forum… ^^