"Everything is better than it was 20 years ago" - yep. Agreed. Totally. Helmets are way better, and way more comfortable.
And, we understand more about concussion, TBI, and CTE than we used to. Absolutely.
But that doesn't mean the statements like, "MIPS’ position on evaluating the possibility of a concussion resulting from a crash is that it is a highly variable event and unique to the individual impact and rider physiology. However, rotational motion itself can be measured objectively, so that is the metric MIPS can actually report and address," aren't textbook McNamara Fallacy.
"I don't think any helmet manufacturer is making a claim that "these devices will save necks and brains", I'd disagree, based on this from Wavecel....
> SLIP helmets significantly reduced the probability of sustaining AIS 2 brain injury compared to CONTROL helmets in all impact scenarios, with reductions ranging from 32% to 91%. CELL helmets significantly reduced P (AIS 2) compared to CONTROL helmets in all impact scenarios, with reductions ranging from 81% to 98%.