Earlier quoted context omitted.
I read the article: if they are, that is quite unclear to me. Possible answers that are discussed are only 'some sort of IP encapsulation', which is vague and GRE, which is just a single solution. He doesn't seem to disapprove of VXlan, so probably something was missing in 'IP encapsulation and GRE'. Was 'all problems solved decades ago' merely hyperbole or is there actually something to it?
Is GRE inadequate? A single solution that solves most cases, is codified in an RFC, and has mature, reliable, performant implementations sounds like a winner to me.
Look, I'm just trying to understand the playing field here, for when the moment comes that I need that knowledge. I don't currently have a need for funky networking between Docker containers, but I do have Docker containers and can imagine a future need for funky networking. The article slams new technologies, but doesn't clearly explain the alternatives, which is what I'm interested in, so I'm asking follow-up questions. There is nothing rhetorical here.