Perhaps, you know, in the past, it was more difficult for those with lower IQ's to survive. Now people with lower IQ's can survive for longer, which is good for them -- absolutely! -- however, it would reduce average IQ's.
That would also suggest, this isn't something bad for civilization like the article suggests. Perhaps the same number of incredibly intelligent people like the ones you mention are better able now in this modern age to get their solutions to more people to make it easier to live.
That's basically saying "there's a systemic trend in this data. Let's hope it's not correlated with other trends in this data".
Maybe it is, maybe it isn't - but until we know the whole dataset is suspect.
IQ says little about the specific skills someone has trained, so more specific tests are useful for that, but it provides a lot of information on the general aptitude it is intended to assess.