Wtf? I've worked mainly for startups, with a couple of large companies in-between, and I've had the exact opposite experience. The engineering in every startup has been fairly lean and efficient with a few mistakes here or there, and every large business has been an 'agile' hell where everything feels ludicrously slow and nothing gets done.
I've always avoided interviewing with FAANG etc because I just assumed they'd be in the latter category with the sheer number of employees they have. It's interesting to hear that Facebook actually runs smoothly.