Judy,
Most of the 'learning' projects spend quite a bit of time to find profiles that the 'hikers' can use. Most of those projects try to find profiles that the 'hikers' will be able to easily find reliable sources for, so they they can 'learn' how to use wikitree, 'learn' how to research, and then 'document' their research into the profiles. The purpose of the 'learning' is not to get people frustrated with the 'learning' process, so it is better to have profiles that they know have sources. Once they have identified some profiles and they put the 'image' or whatever on the profile, hopefully people don't edit them.
If you or anyone comes across a profile and they are part of the family and / or they have found many sources, all you have to do is ask the project if you can update the profile and they will 'probably' remove the 'hiker hold' from the profile. This was stated in the previous discussion by multiple people and projects.
If there were a limited number of profiles on wikitree that needed sources and / or dates and / or locations, then yes, I could understand people saying that no profiles should be held, but there are thousands of profiles that are unsourced, undated, unconnected. I suspect that most of them, based on the work that I normally do, do NOT have the Unsourced template / category on them, so they are not included in the counts of unsourced profiles. There are many profiles that were loaded with gedcoms with no dates and no sources before standards were changed, Therefore, there are plenty of profiles for people to be updating, excluding the less than a thousand 'total needed by all learning projects'.