At first glance, selling WotC seems similar to what happened with Bungie and Halo, but I don’t think WotC is more than just the D&D and M:tG company now. They’re more like 343 Industries than Bungie.
I assume if WotC were sold, it would be to private equity with Hasbro’s retaining the IP rights and licensing them back to WotC. The goal would be to externalize development costs while also turning it into a source of revenue (via licensing). Hasbro could also return some of the proceeds to shareholders, which their institutional investors would love.