"It starts with a lie"
Web Mercator is a Mercator projection, so it's not a lie, just slightly imprecise.
"which is admitted in the very end of the post"
The post discusses Web Mercator in the second sentence.
"The most obvious reason to use web-mercator is it is easily computed."
Which the article discusses.
"For me, as a user, it is inconvenient. I almost never care for north to be exactly on top."
Google maps has a lot of users with various use cases. For uses involving directions, conformal maps are better, and the maps are heavily used for that. All engineering decisions are compromises, Google's compromises apparently were the best for their expected use cases.
Friendly note: you’re using “large scale” and “small scale” precisely the opposite of the way geographers/cartographers use those terms. A “large scale” map is one that is zoomed in on one tiny area, while a “small scale” map is one showing a large region or the whole world. https://en.wikipedia.org/wiki/Scale_(map)#Large_scale.2C_med...
The most obvious reason to use web-mercator is it is easily computed. Probably the real reason to use it now is that people are used to it. Most google maps (or even OSM) users probably don't even suspect there's something wrong with that map, and don't imagine there are other projections. The only people who complain is a bunch of cartographers, and who cares about them, right?
So I don't expect something is gonna change and don't really know if it is easy enough to provide alternative projections for OSM. For google maps at least there's google earth.
For me, as a user, it is inconvenient. I almost never care for north to be exactly on top. I use maps on large scale to answer questions like "hm, so where is that Sahara desert? How large is 9,400,000 square kilometres? How far is the distance between these two airports? What is Cambodia?" To answer these questions web-mercator is nearly the worst projection possible.
On small scale I don't even expect the map to be precise, I just need it to tell me where should I turn to get where I need. So on small scale web-mercator isn't harmful for me, but most other projections wouldn't be either.
Personally I like Kavrayskiy VII projection¹. The only thing I dislike about it is the fact it make Antarctica to look huge. I wonder why it isn't more popular, really.
[1] - http://en.wikipedia.org/wiki/Kavrayskiy_VII_projection