I got married ~3 years ago after several years of dating around. This book really helped me understand the psychology of finding a partner and getting married

Love Factually - Duana Welch, PhD

It talks a lot about playing hard to get. The book basically frames it in the same “more in demand” that this linked article talks about.

And also adds something I’ve always remembered.

We see hard-to-get as attractive because we know, for others, they will be impossible-to-get once they’re our partner.

(I’m paraphrasing)

So hard to get only works as long as we perceive they’re hard to get for others also.

Anyways, that book was definitely a life changer for me so if you’re interested in this kind of stuff or trying to understand the confusing world of finding a partner I highly recommend it.