Your comments

Thank you Jon!

Indeed seems WinSparkle is quite new, and 64bits is in the roadmap.

As for automated installation that can be achieved with InnoSetup, which is what you're using for the installers.

Anyhow, thank you for your answer and analytzing this in the first place.
Your use case. You like to download files and have them lying around, that is your use case.

Indeed is less priority, wanted to add this here, but not for you to downvote, are other things more important.
That is your use case, not everybody.

The problem is doing all that process over and over again, remembering where you placed the download, having several downloaded copies lying around in your download folder, etc.

Sparkle provides this solution for OSX, why Windows should be cumbersome compared to it when is possible achieve the same?

You can still disable that preference if you want.