Any company has a problem, which they size the value that it has to be tackled for, so they set budget, measure options, raise possible trade-offs, eventually succeed at dealing with it or get bitten due to lack of proper future-proofing, not evaluating environment/requirements properly, rinse and repeat. Once you've got several problems that require this kind of approach, carefully handpicking the possibly-but-not-proven best solution is not only time consuming but might lead to potentially awfully impactful consequences. When the decision to switch cloud provider services to one that may get you offline for half an hour leading to a million-dollar revenue impact, that's when we're talking enterprise.
I work in a big lumbering organization. Sure, there is some truth to that. But there is also just a lot of suboptimal decision making, because big organizations have complicated politics and policies, and it is often easier to keep coasting than do something better.
Sure, I am sure they have something to say about how smaller internet companies move fast and break things with no concern for how it affects customers. I am sure you would rather have your bank just work than have some nifty tool with insufficient testing and that flakes out every other day.
Everyone to their own, I am just stating that there is a need.
Enterprises have these processes not just because they like bureaucracy (though they also often like bureaucracy too).