It's not a matter of usurping, really. If I recall, Mudcat MIDIs were for a period stored at a site using that domain name. But when a person or organization ceases renting a domain name, any other entity can grab it and post anything they want there--a great opportunity for phishers and site sponsors to exploit residual traffic from obsolete links.

Also, it often happens that a user or organization, renting space from a hosting service, will close down their site while the domain name is still being rented, and fail to deactivate or redirect the domain name mapping. In that case, the hosting service that originally sponsored the site will still receive any traffic directed to the domain name. It can reroute these page requests anywhere it likes--usually to pages advertising its own services. That appears to be the case here--you'll notice that the page reached explicitly says the domain name is up for sale.