Normal - meaning neurotypical, not severely mentally ill, on the spectrum, mentally challenged, etc. Not to say that some of those women don't also get laid but that's not who we're talking about. Also talking about women with a normal, healthy libido who aren't asexual or otherwise sex avoidant.
Attractive - Above average looks, 5 and above, physically fit. That's not to say that ugly and fat women don't get laid too but that's not who we're talking about.
Young - Women who have been single for any length of time post-Tinder. Not a 50 year old who has been married for 20 years.
US - probably elsewhere too but who cares
Single - Not someone who got married at 18, or someone who has been in a LTR since before Tinder, but women who have spent a lot of time single. Not someone who was in a 5 year LTR and then a 10 year LTR.
Sexually active - not women who are saving themselves for marriage, or asexuals, or anyone else who is choosing not to have sex for whatever reason but normal women who have had premarital sex.
High N count - Conservatively let's say an average of 4 new partners each year of being single. That would mean an N count of 20 accumulated from the ages of 18-22. 65 partners by the age of 30, and over 100 if she's still single by 40. Let's be even more conservative and assume that she had some LTRs mixed in there and cut those numbers in half. That still means 16 by 25, 32 by 30, 50 by 40.
When guys talk about the cock carousel these are the women they're talking about. The PPD women who deny the CC exists most likely aren't in this demographic group because they are old, have been in a LTR for a long time, are not neurotypical, are unattractive, tradcon, don't live in the US, or some combination of all of the above.
The woman described above is normal, and is in the majority. And she and all of her friends most likely have high N counts and consider it totally normal. And they didn't necessarily have to feel like some crazed slut while accumulating those numbers, they just did it via regular dating, being single, and accumulating a few new sexual partners a year over an extended period of time.