The brutal competition for tenure track academic jobs

The Zippia data claims only 9% of adjuncts hold a PhD. Most have bachelors or masters degrees. Seems odd to me. Any thoughts on that? Is this just bad data?
I have a friend that used to adjunct at a community college. She had a masters degree in the sciences and was fine with the part time nature of it. Another acquaintance had a PhD in the humanities (philosophy I think) and jumped from place to place for years before landing a tenure track job someplace. Very tough on him.