I’m really not sure who’s saying that there should be a wholesale change-over for all programs (I haven’t been given that instruction as a unit-level volunteer). As Stephen noted, Cub Scouting advancement moved over wholesale, and units who use a third-party platform that has upload agreements with the BSA have always been using what is now Scoutbook Plus, but used to be “branded” as Internet Advancement 2. Aside from that, all of the messaging that I’ve seen has been that other types of units should still be expecting to use classic Scoutbook (or whatever other tracking solution they have been using). One concern I would have with councils pushing information out to individual users is the potential for even greater confusion than simply having unit scouters – whether that’s the Key 3 or whomever the unit’s tech-savvy scouters are – subscribe to the changelog threads (and/or the BSA Announcements category, which tends to carry the broader-audience announcements) and disseminate that information to the scouts and parents the way we do with scouting program changes (e.g. updates to requirements, etc).
I think part of the problem is that there’s always something that isn’t working (or interacts poorly with a local system), so there isn’t any realistic ability to wait until everything is 100% functional to release. For example, in the pre-Scoutbook Plus (aka Internet Advancement 2) days, when the BSA had just purchased Scoutbook, there were bugs in the system at the time. As those got squashedm, new ones cropped up or new features were added that introduced some undiscovered issue. No software is ever 100% bug-free, which I think you already alluded to in some of your posts.
In addition, though, there are other aspects of the BSA program that (likely) impacted this particular change-over. As Stephen noted, there was a wide-ranging change in how the Cub Scout advancement program was structured. Rather than building that into both classic SB and SB+ (thus having two platforms to make mistakes in and beta test), the BSA made the decision to build it out on the SB+ platform only, since SB is (as you noted) being retired once all of the functions move over to SB+. I could see that contributing to the confusion as to what platform should be in use, and maybe there was some difference in how it could have been messaged that I’m not seeing (because I’m sufficiently familiar and active here that it came across pretty clearly to me).
As to more broad beta testing, there are already unit-level scouter beta testers for the systems, based on what has been posted publicly by the SUAC volunteers, as well as having internal testing by the development team (professionals). I can’t comment on how the beta testers are selected, since I don’t know. There has been some discussion of this recently by @edavignon from the SUAC on another thread, so you might be able to glean more insights if you can traack down that post. SUAC has also noted that the BSA doesn’t have the kind of resources that big-name development companies have to throw at software development. So, it’s probably not a reasonable comparison between large entities whose sole (or at least primary) function is software development and the BSA which as an organization either retains a small outside development firm or hires their own in-house developers to do their software work. Also, while we as scouters may consider the software mission-critical, it’s definitely not life-safety critical, so I suspect that the degree/rate of testing prior to release likely reflects that.
That’s not so say that we shouldn’t expect better long-term stability, or even that there might not be a better job to be done of communicating things. I"m not sure what that solution looks like, but I know that the volunteers on these discussion groups are not the folks making the decisions, so while they may or may not agree with you, they have no ability to alter the process one way or the other. You might be able to get your council professionals to advocate more directly with BSA national for a clearer communications strategy, but you probably need to have a sufficiently detailed explanation of what you think is wrong and how to address those shortcomings to motivate your council to carry the torch for any such changes.
My hope is that the info I’ve shared provides some degree of context (even if it’s largely just extrapolation from information that’s been posted here over the years) for where the BSA is in terms of why some things are happening the way they are. I say that as a fellow unit-level volunteer, since I’m not BSA staff, one of the developers, or anyone particularly “in the know” and probably couldn’t provide further insights at that level even if I had it (NDAs, etc).