Woaw, look at this FLOSS-hostile move by Microsoft. According to their policies they have to take money from people to be able to provide Krita in the microsoft store.
And because of that they write that they can get to the website to get it for free. But Microsoft doesn't like that (may be valid for some type of stuff tho) so now they aren't allowed to talk about downloading it on the website.
https://krita.org/en/item/krita-in-the-windows-store-an-update/
Very unfortunate