I just want to add to Quentin's observations that they do not apply exclusively to NVDA. The general purposes of alpha, beta, release candidate, and stable releases of software are the same no matter what the software or who makes it. Some makers do not use (for the public, anyway) alpha or release candidate steps. The "public testing" version is the beta, and there can be several betas as different kinks get worked out.
The idea that either alpha or beta software are "sneak peeks for the curious" with no obligation on the part of those who elect to use them to report issues needs to die a very quick death. Alphas are generally for the development community, almost exclusively, with betas being for the end user community that's willing to put up with instability and bugs, and report those, as part of getting an advance look at what's happening next.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
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