Like you would pronounce it in Latin?

I mean, it's wrong, but in the too-educated direction, not the not-educated-enough direction.

You misunderstand me - I am saying he pronounces the 't' in 'et' like a K.

The fact that the c in tacit is usually pronounced softly is tacit knowledge

Many classicists believe the Latin C sounded like our K. So you get words pronounced like Kaesar, ketera, kivis, etc.

Pretty sure the comment was about the video narrator pronouncing it "ek setera", not "et setera" or even "et ketera" (I counted 3 instances). And I agree, just like people who say "supposably[1]", it exposes somebody who isn't well read.

[1] - https://www.youtube.com/watch?v=-qsJzB74N7o

or "ex etera"

that's an (historical latin pronunciation is a subject of some debate) acceptable latin pronunciation of it.

Tomato tomato. Maybe he thinks his way is funner to say.