Confirming source-routed multicast is dead on the public Internet

Its tought to prove a negative. I'm extremely confident the answer is yes, public internet multicast is not viable. I did all the google searches, check all the usual CAIDA and ISP sites. IP Multicast is used on private enterprise networks, and some ISPs use it for some closed services. I got sent back with a random comment from a senior official saying "but I heard different." I bit my tongue, and said I would double (now quadruple) check. If any ISPs have working IP source-routed multicast on the public Internet that I missed, or what I got wrong. That's what content distribution networks (cdn's) are for instead.