The following things can be (and I believe are) true at the same time:
1. It's misogynist to think Chepngetich's performance today ruined the sport when Kipchoge and Kiptum have already run 1:59 - 2:01, and the women's world record tends to be around 9-10 minutes slower than the men's. She just ruined women's marathoning. Men's marathoning was already ruined, unless you think what ruins it is only for a women to finish very high among the men in a WMM.
2. Chepngetich's performance today was an improvement on her previous times, but it didn't come out of nowhere. She's been progressing consistently toward a performance like this for some time.
3. Kipchoge's, Kiptum's, and Chepngetich's performances are all impossible without PEDs. Chepngetich is just the latest to be doing what they were doing, and to respond to it as they did. Whatever she's taking, she did not just start taking it. It isn't new.
Watch the interviews of other athletes who ran Chicago today. Many of them complain about the conditions not being ideal for fast times today. Chepngetich can run faster still, as could Kiptum apparently. So:
4. Either some athletes are super-responders to this drug / these drugs, or some unusual training methods produce a super-response to them, or (less likely) they are available only to a small number of people (but have been for some years now).