Sometimes you find yourself at the end of a deep rabbit hole and you ask yourself how did you get there. It is tempting to think that the problem is with you doing a zig while you should have done a zag but rarely you hear people asking what exactly was Alice doing outside by the river with no parental supervision in the first place?
It is pointless to discuss several of WordPress sins without understanding why they came about, and why there are not ever likely to get fixed.
In the beginning, in the good old days when WordPress was just a blogging platform, it was easy to understand the guiding philosophy – make web publishing easy and accessible to all. This motto worked well and in an era in which you had to have some technical knowledge in order to even buy a domain, it was a major factor in WordPress’s success and in the flourishing of blogging.
Then, two things happened, WordPress decided it wants to be more than a niche blogging platform, but an actual CMS, and Facebook (and to lesser extant twitter) came and killed blogging. This caused a shift in perspective, WordPress do not measure itself anymore in how many bloggers use it (that ratio is declining due to people preferring to “blog” to their friends on Facebook instead of addressing unknown audience), but in how many installs it has.
The problem is that in too many cases quantity and quality do not go hand in hand. It might not be a problem if every decision being made is the right one, but it makes it impossible to change anything for the better if it means that someone’s site will stop functioning. This is true for every type of software but it is even more visible on the web where everything is almost always in a flux.
When you claim that 27% of the web is powered by WordPress, and give the (disputed) number importance it is very easy to see why you are not going to do something that will annoy about 5% (at this point in time) of your users by doing the right thing and dropping support for the EOLed and generally insecure PHP 5.2.
It is actually worse, as with PHP 5.2 there are at least mostly reliable stats on the amount of people that are going be be impacted from a deprecation of support, but there is no usage collection for almost any other feature, and no one dares to suggest changing or even deprecating any of them because the impact is literaly unknown. This leads into the worst kind of stagnation, where even bad decisions has to be preserved.