Sure. However I don't think he's promoting security through obscurity so much as figuring out his threat model and risk acceptance. For most businesses and end users who love Zoom, everything else they've tried has failed to do the thing acceptably. Like, they probably are more secure in so far as not enough people can successfully use them, so doing no video conferencing is more secure than doing some video conferencing.

And to be honest, most business stuff is by unencrypted e-mail, so I don't see how a TLS encrypted Video Chat increases their exposure.

Finally, the chance of someone, even zoom, recording and analyzing all the video conferences ever to somehow get important info from a video conference seems pretty low anyway. Unless you're worried about the NSA, and even then, it seems like they'd have a way into WebEx etc also, so even on risk.

At this point, it seems reasonable to go by what works for people. And Zoom works.