Audio or video social media networks exist? (do not write but speak + mass audio conferences)?

Question

Audio broadcast

the current generation of social projects is barely popular
where hundreds of people with hundreds online participate in audio conferences
, and even more so in video conferences
audio conferences for 100 million participants is technically prohibitive?
what limits could be on the number of participants in an audio conference?
just like online radio and listeners connect one by one to comment on the broadcast ...
then how many listeners can there be?
for example, a channel of 15-100 Mbps and broadcast quality mono 10kHz 16bit
well, and make repeaters like in a torrent
(audio files for 20 seconds are cut and relayed over the torrent network to other participants so that there is no load on the outgoing channel of the broadcaster)
then listeners 1-100 thousand?
in general, has anyone heard about huge audio conferences?
Kotlyarov?