Because they are prioritizing data collection over performance.

Windows is no longer about giving customers a good operating system. It’s now a vehicle for Microsoft to collect data from you for them to use and sell to other parties at a profit. It’s why Microsoft hasn’t cared much about pirated versions of Windows much anymore. They’ll do small things to annoy you, but overall, you can still use it and they still get to collect their data.

Microsoft is only starting to be more concerned as Windows loses market share and Linux gains some. The Steam hardware survey has only gone up a few points of percentages but this accounts for thousands of losses and this only shows gamers who use Steam, not all the other use cases.

So Microsoft is finally starting to make some promises to improve performance now that they have some real competition. And they’re only doing that because they want to continue collecting your data.

That is what Windows has become, unfortunately. Your performance while using it is very secondary, if not at all a priority of theirs.