Example: 20ish years ago, stage IV cancer was a quick death sentence. Now many people live with various stage IV cancers for many years and some even "die of sending else" these advancements obviously skew towards helping older people.
The reason humans die of 'old age' is not because of any specific disease but because of advanced senescence. Your entire body just starts to fail. At that point basically anything can kill you. And sometimes there won't even be any particular cause, but instead your heart will simply stop beating one night while you sleep. This is how you can see people who look like they're in great shape for their age, yet the next month they're dead.
But the results remain modest. The biggest breakthrough was in the 80s when somebody was able to roughly double their life expectancy from 2 months to 4 through artificial selection. But the context there is that fruit flies are a textbook 'quantity over quality' species, meaning that survival is not generally selected for, whereas humans are an equally textbook 'quality over quantity' species meaning that survival is one of the key things we select for. In other words, there was likely a lot more genetic low hanging fruit for survivability with fruit flies than there is for humans.
So I don't know. We need some serious acceleration and I'm not seeing much of anything when looked at with a critical eye.
The overwhelming majority of all gains in human life expectancy have come due to reductions in infant mortality. When you hear about things like a '40' year life expectancy in the past it doesn't mean that people just dropped dead at 40. Rather if you have a child that doesn't make it out of childhood, and somebody else that makes it to 80 - you have a life expectancy of ~40.
If you look back to the upper classes of old their life expectancy was extremely similar to those of today. So for instance in modern history, of the 15 key Founding Fathers, 7 lived to at least 80 years old: John Adams, John Quincy Adams, Samuel Adams, Jefferson, Madison, Franklin, John Jay. John Adams himself lived to 90. The youngest to die were Hamilton who died in a duel, and John Hancock who died of gout of an undocumented cause - it can be caused by excessive alcohol consumption.
All the others lived into their 60s and 70s. So their overall life expectancy was pretty much the same as we have today. And this was long before vaccines or even us knowing that surgeons washing their hands before surgery was a good thing to do. It's the same as you go back further into history. A study [1] of all men of renown in Ancient Greece was 71.3 [1], and that was from thousands of years ago!
Life expectancy at birth is increasing, but longevity is barely moving. And as Kurzweil has almost certainly done plentiful research on this topic, he is fully aware of this. Cognitive dissonance strikes again.
[1] - https://pubmed.ncbi.nlm.nih.gov/18359748/