They're not ignoring anything, they're disagreeing with [what they perceive as] your implications. Because while some injuries that would have caused deaths cause lifetime damage now, injuries that would have caused lifetime damage cause a lot less of it now.
this might be the case, obviously advanced arthroscopic procedures can improve results that in the recent past would have been lifelong problems, but not sure if the benefits of modern medicine across all sorts of battlefield problems are so evenly distributed, I think not given generally the articles I read seem to be echoing my point and not saying that but it all evens out because of this additional benefit, but maybe.
Given that I believe my point is pretty commonly argued and his rebuttal does not seem to me to be as commonly given I would have liked a link to "army study showing the percentage decrease of what were serious injuries match pretty evenly the percentage decrease of what fatalities, showing an even distribution of medical improvements across the range of possible trauma", something like that.
Obviously depending on what was meant by "survivors in past times" applies here, because that is a pretty long range of time.
on edit: my googling shows lots of discussions of improving should injuries that used mean disability are now trivial and so forth, but not overall stats showing the decrease in overall battlefield injury significance matches the decrease in overall battlefield fatality to a reasonable degree.
