> Why are we integrating "msstore" only application into a business focused product like Intune/Endpoint Manager?
Because only the Microsoft Store provides an official path for software with a robust validation mechanism. The community WinGet repo has many similar checks and validations as the public Microsoft Store, but they are not identical and thus the WinGet community repo is just that, a *community* based repo and not an official repo. You should consult with or ask the publishers of the software you called out why they don't publish to the official Store as that's not a question I (or we/Microsoft) can answer.
> Why are we not integrating "winget" sources?
We are planning on it, just not the community repo. This is a high-level decision based on the fact that the community repo, as called out above, is an unofficial, community repo.
> Why are you promoting this as "winget" when it's clearly just "msstore"?
Because it 100% uses WinGet and as noted, there are plans to add support for private WinGet repositories. There was an early aspiration to add support for the community repo, but those have more or less been deprioritized and may never be realized.