"Action speed cannot be modified below based value" Doesn't work with vines

If vines are movement based and action speed doesn't affect it, then cannot be hindered should work?

It doesn't though unfortunately.

Vines aren't "Hinder" either.

"Hinder" is a specific effect that gives a movement speed slow. Not all movement speed slows are Hinder.

Similarly, not all movement speed slows are Maim, either.

Maim is generally applied by attacks while Hinder is generally applied by spells.

Perhaps "Ensnared" could be a new category of thing, so that you could have something like "50% reduced effect of Ensnares" or "unaffected by ensnares" and such. That would be something to put in Feedback and Suggestions, however.