Part of his argument for sure.

Other argument is that we could create sidechain providing great privacy.

Issue with this arguments are two in my opinion:

1. We can achieve really great privacy on regular L2s and lightning as well. It just needs some time.

2. Due to small anonymity set on sidechain the privacy is highly questionable anyway.

So yeah, I don't see any argument sufficiently strong and urgent in my eyes. But what do I know, I'm just 80IQ pleb.