Flexibility is also a feature

Evolutions need to be careful about not losing flexibility because flexibility is one extremely important Git feature.

For example, while it's understandable that reftables can certainly speed up certain operations and/or solve naming problems (BTW aside FAT/NTFS, how many other FS are case insensitive by default to call that "most" ?), being able to grep/edit/add references directly in the refs/ directory *is* a useful feature. Granted it's not used every day, but when you have to do it, it's because you have no other solution. I'm a bit worried about the wording like "users need to make sure they're not doing tricks such as...". Because it's not necessarily "tricks", it's just regular operations that correspond to their legitimate workflow, and when they do it because they need it, they're left without any option left once the feature is removed (except staying on an old version forever of course).

I think instead the speaker should rather say "those who rely on this flexibility should contact us and explain what they're doing and why they need it so that we can see if some new features are needed to ease the manipulation of refs".