Can Chill Touch prevent Regeneration?

Question

Can the D&D 5th Edition cantrip Chill Touch prevent regeneration and similar abilities?

Do specific forms of regeneration (like a troll's) circumvent this?

Chill Touch:

You create a ghostly, skeletal hand in the space of a creature within range. Make a ranged spell attack against the creature to assail it with the chill of the grave. On a hit, the target takes 1d8 necrotic damage, and it can't regain hit points until the start of your next turn. Until then, the hand clings to the target.

Troll rule text:

The troll regains 10 Hit Points at the start of its turn. If the troll takes acid or fire damage, this trait doesn't function at the start of the troll's next turn. The troll dies only if it starts its turn with 0 Hit Points and doesn't Regenerate.

(emphasis mine)

Here is the now-unofficial ruling from Jeremy Crawford.

I can't tell if this is a classic case of specific-vs-general or just designer intent being unclear in RAW.

Answer 1

Yes, chill touch prevents regeneration. The spell's text says that the target can't regain hit points, and there's nothing in the text of the troll's regeneration feature that contradicts that. Just because the trait doesn't function if the troll takes acid or fire damage doesn't mean that's the only condition under which the trait doesn't function; saying otherwise is affirming the consequent.

Answer 2

Only partially, and not permanently.

Regeneration here has three effects:

1. The troll regains 10 Hit Points at the start of its turn.
2. If the troll takes acid or fire damage, this trait doesn't function at the start of the troll's next turn.
3. The troll dies only if it starts its turn with 0 Hit Points and doesn't Regenerate.

Chill touch directly prevents 1 as stated, but it neither fulfills 2 nor otherwise prevents 3.

The net effect is that, absent acid or fire damage, the troll won’t regain hit points until it’s no longer under the effects of chill touch, and will then start regaining hit points.