Is this necessary if HTTP2 is enabled

[rossmc]

Just wondering if this will be necessary if you're using HTTP2?
https://http2.github.io/faq/#why-is-http2-multiplexed

Any thoughts?

[Januszpl]

Yes. It helps to set some critical code to load first. By default in Magento2 you can wait longer for having interactive menu (especially on mobile). Using this you can tweak things like that.

[joshuaadickerson]

Even with HTTP/2 you will still have a lot of latency waiting for each script to load. In addition, Chrome and FF limit the number of concurrent requests. Not sure about other browsers but I know in those two you will see a notice after (I think) 30 concurrent requests.