Is Hex worth it at high levels?

[Blatant Beast]

It appears to be left to the reader to assume what they do or do not involve.

But, Spells do what they say they do…so if something isn’t specified in the spell description it does not happen. If this is not true, then the correct answer becomes “ask your DM”, which makes all D&D discussion a matter of talking about homebrew, so there has to be a singular answer, a singular way to rule, and always be correct..because without that all communication becomes pointless…;)

I think that sums up a common response when it is pointed out that 5e, as a base unit of operation, relies upon the participants’ judgement.

This is not uncommon in 5th edition. For instance, on PHB pg151 for putting out a fire, it says "A creature can end this damage by using its action to make a DC 10 Dexterity check to extinguish the flames." This presumably involves you actually physically doing something to extinguish the flames, but it doesn't actually tell you that. It just says you can use your action.

Stop, Drop, and Roll being a well taught procedure, it is easy at least to envision a PC trying to at least pat out the flames.

It is also trivial to imagine what a Cunning Action usage looks like…when the Rogue takes off in a mad dash. An anime based game may even add speed lines.

I think it is fair to say a Bonus Action ability such as Second Wind, is harder to visualize, or indeed might be commonly conceived of as having no visible phenomena to denote the ability being used.

A Second Wind Activation could look like a Fighter wiping sweat off their brow, or just be described as the Fighter appearing to be in contemplation for a second, or nothing at all.

It certainly seems reasonable to me, at least thematically, that transferring a Hex spell might involve some small physical action that could be detected by the discerning observer.

Ruling that transferring a Hex spell, requires the caster to glare at the new target, seems appropriate given one common hex described in folklore, is the Evil Eye.