It's 2019 now though. only 8 years later, but a lot of things changed.
The industry is growing fast, faster than knowledge can be shared even with all the power of the internet. It's very bottom up, with newer engineers severely outnumbering those that have been around. People are making fat salaries and companies are catering to their whims. They/we're more spoiled than they've ever been. People go to work hoping they'll be find a reason today to try the latest pattern they saw on Twitter or try the trendy new tech or library their friend just talked about.
If you don't have people saying no, it quickly (very quickly) get out of control. As organizations grow, you need to start saying no. A lot. Else within 0.2 seconds of the new intern joining or the new grad coming in, or the lateral hire who was the king of their 5 people startup will be pushing some stuff that isn't mature enough or doesn't follow established patterns. More often, they'll be reintroducing something problematic that you just finished getting rid of 6 months ago.
It sucks. Sure, there are some power hungry people who get off on power trip by being gate keepers. But overall, it's just people desperately trying to keep things in one piece and the company going, and that means making hard decisions and enforcing them. It just doesn't feel good to say no, arguing all day with people who have way more energy than you do, but it has to be done.