Chromecast actually mostly sends a link to a google device and then launches it on the device to play; there isnt a direct replacement to that.

I'm aware of one project called ScreenInvader but it's unmaintained since about a decade. It offered a web UI where you could paste a URL from any device:

As you can see the UI was clunky and I guess it's part of the reasons why it died. Too bad, I like the concept of having a jukebox at a party where people can just contribute to without installing anything, let alone sign up for an account.