"We discussed this change a lot (most recently here and here) but I realize it will be jarring, and not everyone agrees with it." - I gather that this is why this decision was just made, because all the pro's and cons could not be weighed in time; it was not in anyone's interest to make time.
"An important point that emerged in our conversations is that categories aren't just for us. They're not just for genealogy collaboration. They are part of the genealogy content that we're growing and what makes it accessible to others, now and in the future." - Yes indeed, that is why Projects started implementing "Maintenance Categories" so that it becomes clearer what needs to be done and to which project a profile belongs, so that it may be optimaly managed.
"For example, categorizing people as farmers may seem genealogically meaningless and overly broad for any practical purpose here. But some future descendant might want to see all their ancestors who were farmers, or some historian might want to see farmers in a certain geographical area." - In that sense we are speaking of tags, not important categories. If I go to the category "Farmers", I'll find a vast pool of profiles with exactly that. The idea of maintenance categories is that when one arrives on a profile, that it is obviously visible what is needed to be done. Going to the holding pen of a specific category such as [[Needs_Marital_Records]] is working the other way around.
"Categorization is very useful for search and navigation, but the usage of categories has been constrained because members have only wanted to use them for genealogically important things - things that merit appearing above the biography. Their overly-prominent position made their usage controversial. Now I think members will feel more comfortable seeing them used more liberally." - This does not make sense to me. The logic here seems constrained and not factual. How will 'more' members feel 'more' comfortable when members [anyhow] 'only wanted' to use them for 'genealogically important' 'things' {{Sic!}} Also, following this seemingly non-sensical logic, the DNA-test info also need to be to the bottom.
"By the way, all this is about their appearance on the profile page. The placement of the category tags when editing a profile doesn't need to change." Yes, this is overly clear. When I edit a profile, the categories still appear above with the edit frame. But the maintenance categories, even when encapsulated within a template, does not show up at the top but at the bottom, when the edit is saved and the page returned to normal view. Right down below the rest of the i.m.h.o. junk such as so many steps removed from such and such …
Only if a profile is protected, there is an inkling (in our project at least) that at least some validation has taken place, even though what is still needed is then information on other needs, such as marital or death records.
I have - as some people below, suggestions that might alternatively or by way of compromise be useful.