This can be especially heartbreaking when one has to take a time off just to appear in city Y, spend money on transport, and then find out that the only person that can accept the application has not arrived to the office, and so the whole trip was for nothing (personal experience).
Countries seem to have a hard time explaining spending money on efficient dealing with immigration. The whole immigration process is highly stressful even in the EU; I can't imagine how stressful it is in the US, which treats immigrants quite poorly (in my humble opinion).
Add the factor that the public service does not have the same kind of incentives (and being a native of the country makes you know about the ways of making things work - foreigners don't know that usually)
Granted, not all countries are like that. And while people might complain about German bureaucracy, they at least make an effort to do things by the book (meaning: if your appointment says a certain time, you'll be seen at that time)
And American bureaucracy also has its quirks and complications when seen from outside.
The case where it isn’t is for people not born from French parents or not married to a French citizen (plus a couple of other exceptions). In this case, the criteria for naturalisation are clearly spelled out in the law. It should not be arbitrary.
The current mess is because governments want to limit immigration without touching the law to tighten the criteria, for purely political reasons. The French government actually knows how to run large administrations quite well when there are incentives to do so.
It took roughly the same time for almost everyone that I know that applied. The only cases that I know of that took longer were people with "exotic" statuses, e.g. people who didn't live full time in France and owned businesses in different countries that they had to visit often to physically tend to.
My gf is applying for citizenship at the moment, I've described the timeline for her situation. It's been now more than 3 years since she started her application, including 14 months waiting for their decision. And she'd been living in France for more than 10 years before that and graduated from a French university.
It probably would have been easier to just get married...
BTW, congratulations for your citizenship. I'm glad it was efficient for you.
So by the time you are eligible, it can take 3-4 years before you know the outcome of your application. These 3-4 years don't serve any obvious purpose that I can think of.