I'm mainly interested in those people who became co-hosts with someone or several clients through other means, where the only option available was to be added to the co-hosting waiting list, thus, leaving them to promote their services elsewhere.
Sometimes, people just want to work with someone they have built a relationship with, with someone they trust and know would do a great job managing the listing according to its unique and specific needs.
If I were a host, I would seek within my own network before I turn to the open pool of hand-selected co-hosts that Airbnb is curating.
I'm glad for this feature of Airbnb either way, especially that it's not solely a first come/first served opportunity and allows for many avenues to get into hosting/co-hosting on the platform.