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.
What happened to just good old OS APIs? You could wrap the entire "secure update" process into a function call. Does Windows somehow not already have this?
The problem is that this needs strong regulation to prevent it from turning into a payola marketing scam where vendors have to pay for placement.