I think NI shares a lot with the community. There are a lot of internal details about LabVIEW in the NI KB. There are special INI tokens documented, how we flatten data, how LabVIEW behaves in a lot of solutions. You might want to look through some of our KB articles if you're curious about the internal workings of LabVIEW.
However, I do not think that alpha releases are for incomplete features. Just because we have a feature that's half-done doesn't mean that everyone should be able to use it. There are good reasons we don't finish some features -- they aren't stable enough, they're too resource-expensive, they don't meet the needs of our customers, etc. If we release a feature, we will support it. We still support some decade-old hardware. NI has great technical support. But we can't support everything. I don't speak for NI, but I suspect we would rather support everything we release rather than release everything and have holes in what we support.