Marketplaces are very much alive, especially those that intersect talent and opportunity. Venture Firm NfX has a nice breakdown of the modern mature marketplace, which they call a "Market Network". Here is their blogpost on the topic.
Essentially, a Market Network has three components: Community, Marketplace and Tools. They feed off of each other and maximize the value of network effects, creating a great market opportunity and defensible mote.
Many of these Market Network have Talent as a key component of at least one of the marketplace dynamics they are looking to monetize and add value for both the community and their customers.
One key miss in many of these marketplaces, is in how to think about their big P "Product". In many software firms, where many of these founders come from, software is the product. Things that are human-heavy get lumped into an "other" bucket, sometimes living in a revenue function but most of the time silo'd into ops.
This is a mistake. Revenue is revenue and all companies that have paying B2B customers need to host those functions under one leader focused on B2B. Ops stuff doesn't belong in that org, even thought structurally those teams share some of the same challenges.
So where does Ops live in a Talent Marketplace? It's product. It's product all the way down from sign-up flow to successful transaction, including all of the humans that may be in the process.
Many product managers may be reticent to take on large human teams even if they are integral to the product experience. Talent Marketplaces need to find PMs that are willing to own Ops orgs and are committed (goaled) in achieving increasing marketplace success, NPS and efficiency across both software and human touches.
By integrating the Product and Ops orgs into a single structure, the big P "Product" will better be able to achieve scale and unit economics that make sense for the business and in doing so create an integrated product experience that will drive higher NPS, retention and word of mouth for their talent community.
Product at a software firm can be focused on software. But product in a Talent Marketplace, where value resides in transactions, connections or hires, needs to have purview over both the in-software experience as well as the human touches necessary for the marketplace.
Make sure this is baked in early. Only once a marketplace is scaled and the minimal set of necessary human components have been identified and codified into process can a B2C customer support or success org be split off from product and run separately.