Blessed Strike triggered by Word of Radiance

I've seen a few questions regarding Blessed Strikes with various features like second attack or eldritch blast, all of which said Blessed Strikes only affected a single creature because they were separate attacks.

My question is: How does this work with Word of Radiance if you hit multiple creatures? Blessed Strikes doesn't say anything about only being able to affect 1 creature, just that you can only deal that damage once per round.

Word of Radiance

Casting Time: 1 action
Range: 5 feet
Components: V, M (a holy
symbol)
Duration: Instantaneous

You utter a divine word, and burning radiance erupts from you. Each
creature of your choice that you can see within range must succeed on
a Constitution saving throw or take 1d6 radiant damage.

Blessed Strikes

You are blessed with divine might in battle. When a creature takes damage from one of your cantrips or weapon attacks, you can also deal 1d8 radiant damage to that creature. Once you deal this damage, you can’t use this feature again until the start of your next turn.

This wording is consistent with spells like Shatter:

Shatter

A sudden loud ringing noise, painfully intense, erupts from a point of your choice within range. Each creature in a 10-foot-radius sphere centered on that point must make a Constitution saving throw. A creature takes 3d8 thunder damage on a failed save, or half as much damage on a successful one. A creature made of inorganic material such as stone, crystal, or metal has disadvantage on this saving throw.

So really, I guess it may come down to whether or not this added damage from Blessed Strikes counts as a single "activation" or if it would be each creature individually. I kind of feel like it would've been easy to specify something like When a "creature takes damage from one of your cantrips or weapon attacks that target a single creature…."