The menus seems to be quite 'progressive', there is no way to go back nor to select specifically
Quite, it gives it a certain atmosphære, and it forces people to look at all things against their will as an added side-effect.
The site and most things written seem to deviate from normal spelling or grammar standards, often being very purist or 'pædantic', one could argue that this is no longer English.
And one is quite correct, the author never claimed it to be English here, it depends on the assumption that it's mutually intelligible with English, the rationale is not to be falicious simply because many people are falicious to 'fit in' and bow to peer pressure. if English is falicious then the author shall not speak English.
The site is dependent on javascript enabled, some people would rather not use javascript.
Then they cannot use the site, some people also rather would not use any browser other than internet explorer 6 and can also not use the site. If people have active the requirements to properly view it or not is their own business, javascript support is readily, freely and openly available, its specifications are open and it's a widely known and supported scripting language. The author fails to see why it cannot be implemented.
The 'cropping' of images are just backgrounds in 'p'-elements that most browsers would load in total without really seeing most of it, it could be done more resource-effective.
The images are displayed at a random position and are cached on the server, they are automatically scaled and desaturated once and then reloaded from cache. It would provide significant server overhaul to repeat this process each time and crop them as well, or simply to reload the images and crop them randomly each time. If one's speed is decent it should take less time to load it in this way, especially on busy times on the web host.
Some would argue that the font is too small and too dimmed to be read effectively.
One can zoom in and completely præserve the layout integrity, all dimensions are relative to the font size.
Why does the site use CSS 3.0 when it's not yet a W3C recommendation?
The author recognizes that it is a standard regardless if the W3C recomments it or not, most likely the W3C has never seen this site and thus cannot properly assess what to recomment for it.