Speaker is an analyst and uses several numbers (Tiobe, mailing lists, Stack Overflow, GitHub) and examples (Netflix) to show:

a) that Java is over its peak because it has to tolerate much more languages (JavaScript, Ruby) then in 2006

b) that Java is not in decline, but at least sustaining its popularity and if you include Android you could say the 'Java semantics' is growing.

Speaker continues with some examples of frictionless technology stacks/products, and argues that Java is not that. To sustain growth it needs less complexity, better package managements, compatible licensing, low cost Java hosting.

Finally, some languages got popular by the web frameworks (e.g. Node.js, Django, Rails). But Java web frameworks are too fragmented (due to its long history as a popular language and platform). Java should take its cues from those.