So I've been doing some disambiguation of the grub tag, replacing it with grub2 or grub-legacy as appropriate, And I have done tag only edits to just shy of fifty questions, with no problem until I tried to edit Boot-loader to boot to an encrypted partition. This question would not let me make an edit without a six character edit to the body. So what is different about it?
I think because its been marked as a duplicate.
You need to do a significant improvement, and this is just making sure that your edit is a reasonable amount.
In general when retagging, please make sure that you're making your edits count. If there are typos etc. fix these too. When 3+ people edit a question and/or answer and there have been 10+ edits the question or answer switches to community wiki.
As both a questioner and answerer on the site I'd appreciate it if my write-ups didn't go into community wiki mode, I like to retain some control over them. I think others would appreciate this as well.
Community wiki questions and answers generally fall prey to "abandon-ware", in my opinion. If you go looking around the SE sites, they're usually not well kept once the original author loses either the enticement to keep their products up to date through upvoting, or they get too many voices and become difficult to follow.