I'd argue that the one tool you need is something like git to make those small isolated snapshot copies for you. Learn a few commands and you won't have to worry about an ever-growing pile of directores that will just metaphorically topple over eventually.
Then you can make changes ad hoc with confidence that you can quickly and easily revert if something breaks, without having to organize a smattering of cloned directories yourself.
I guess what I'm saying is, the highest ROI for version control is to learn git add, git commit. At least you have the history well-organized for you down the road, with minimal effort on your part. If you need to revert at some point, you can just figure it out when you need it.
To be fair that's a failing of the git user interface. Giving up on the entirety of version control because one of them has a bad UI seems like overkill.
So instead of using a tool that does all this for you, he should do it all manually, himself, in the most tedious way possible? I mean if he was aiming to learn about version control this might be a good approach to teaching the pains that it solves, but git does all this with approximately 4 pretty painless commands: git add, git commit, git log, and git diff.