I'm not sure, as an investor, that I'd use the term "Titanic" as a descriptive but instinctively, I feel Marc Andreessen is right about audio becoming much bigger over time.
Humans have communicated through voice for a very long time so our ability to convey information, emotion and humour through speech is much more finely tuned than through the written word. As a result, developing a connection with an individual through audio is far easier than through other media, which is probably why we make so many sales calls.
It will be fascinating to see how audio develops over the next few years in a B2B marketing context and whether there is a rise of a few "broadcasters" along the lines of the YouTubers or a more fragmented approach, designed to bring what are today sales conversations into the buying process earlier.
“The really big one right now is audio... Of course, speech as a [user interface] is rapidly on the rise. So I think audio is going to be titanically important.”