It's called Marketing. Everything is 'BS'.
Yes, that's the obvious function but (and I'm just hypothesising of course) we don't know if that tread may also deflect debris at the same time. If it does, the claim has an element of truth
I'm the world's greatest cynic tbf, the statement is exactly what it sounds like, someone trying to Bull up a description to make it sound better. Doesn't mean it hasn't a grain of truth.
And tbf, the claim 'may' be BS. We'll likely never know for sure how that claim is / was / could be substantiated...equally, we have no evidence whatsoever that the claim is true or untrue so its a bit of a mute point really.
It's a tyre, you choose to buy it on its merits, recommendations or gut instinct, price point, or maybe because you like the sidewalls
Imagine, any tyre manufacturer could claim puncture resistance, any manufacturer at all, of the worst tyres even, simply because it places a barrier between the inner tube and road surface and that in itself offers some puncture resistance.
It's all Bull of course, all advertising is, you just need to be able to see past it .