Cloudinary, Imgix, Uploadcare (which I' working for) and others save you money because you don't have to develop and maintain these moving parts. You have to constantly check what's happening with browsers, what formats/encoders are available and which are the best etc.
It's classic build vs. buy dilemma. In majority of cases it's much more cost effective to buy.
BTW, Uploadcare doesn't charge for file processing at all, only for CDN traffic. So you can create as much image variants as you need.
I totally agree, but this was one of the requirements of the editor to have a "good marketable" headline. And we have to admit that this worked quite well.
On the other hand I feel that the article is very light and is indeed more for layman audience :) In depth one would be 10-15 times longer (and 100 times harder to write).
In the article we tried to convey the main idea behind that — take the best tool for the job at hand. There's no "one size fits all" framework or product to put you money on. It's much easier to handle this zoo than making something do that it's not supposed to.
Furthermore, to get high scalability, you have to make things as loosely coupled as possible. This means you're up to making some choices.
well, there's svg)
as for raster, first, I don't think you can have infinite sizes as in vector in feasible manner, second, progressive jpegs are already there, maybe we need to teach clients to stop downloading more info when there's enough for certain container.