Multicast tends to be seen as more modern and "better" than broadcast. In IPv6, broadcast doesn't work at all: you must always use multicast. Nonetheless, all IPv4 local network discovery protocols end up using UDP broadcast anyhow. The reasons: broadcast and multicast end up working much the same, except broadcast is simpler and less risky. Multicast is seen by network admins as kind of dangerous, as it can leak over network segments.
Implement the Cooperative Discovery Using UDP Broadcasts example.