What's concerning is the 6-month window. Supply chain attacks are difficult to detect because the malicious code runs with full user permissions from a "trusted" source. Most endpoint protection isn't designed to flag software from a legitimate publisher's update infrastructure.
For organizations, this argues for staged rollouts and network monitoring for unexpected outbound connections from common applications. For individuals, package managers with cryptographic verification at least add another barrier - though obviously not bulletproof either.
The crappy installation and update channels are often tightly integrated with the vendors' monetization strategies, so there's a huge amount of inertia.
Microsoft Store could have changed this situation, had it been better designed and better received. Unfortunately, nobody seems to use it unless they have no other choice.
WinGet looks much better, but so far it's only for developers and power users.
But then, in an environment dominated by corporate IT who have no real means of switching, why improve the product?
Suppose, for example, that they caught up to where Debian was 30 years ago and Windows shipped with a default list of sources for the core OS to which you could add your internal or preferred partners (e.g. Adobe in many companies). Literally millions of systems wouldn’t have been compromised because they had unpatched apps. If they’d had a curated list of responsible vendors, multiple generations of people wouldn’t have been trained that it’s normal to run installers because a web page told you so.