It seems to me that much of the article can be boiled down to the fact that the standards are being set by people writing software that a) has to be usable by

It seems to me that much of the article can be boiled down to the fact that the standards are being set by people writing software that a) has to be usable by users with the lowest common denominator of tech savvy and b) doesn't have to parse URLs out of other text because it encounters URLs only in defined fields As a result, this software is written to be lenient about trying to interpret URLs input by the user. So it already has to have facilities to transform URLs with improperly encoded special characters such as spaces. This allows it to in turn be more lenient about what it accepts from servers. With no clear standard for these transformations and the browser makers not sharing their parsing and transformation libraries, the writers of other software that has to deal with URLs are left playing catch-up and trying to reverse-engineer the browsers' undocumented hacks for dealing with not-very-well-formed URLs. Moreover, many have the additional burden of having to be able to parse URLs out of other text where the delineation of URL start/end may not be clear. Some of the forms supported by browser makers (who don't have to do this) can't reasonably be supported in this context, leading to frustration for developers (let alone users).