You can change the reported UA header independently of the UA you use.

> I wonder if they really mean a HTML and Javascript engine?

When I say that I mean investment into features in the browsers chrome, directly working on the website.

Yeah, what IS preventing you is the lack of competing browsers.

> And author says social media companies was a positive thing. Sheeeesh.

The author never claimed it was positive as in "morally good". He said it as in "you can make good money with that".