As a former Rocket employee who came from gleaming big corp, I used to think that, but later realized that the slightly more aggressive, chaotic culture was fairly typical of the startup world. Big companies have had the resources and time to iron out HR and management issues over their half century of existence...
When you look at it more closely, the Samwers have effectively managed to reallocate billions of dollars into startups all over the world in places where raising money, or working for a startup, was practically impossible. Remember the second largest location for venture capital funding, the UK, only receives about 1/20th as much as the Bay Area alone.
The more mature Rocket companies (btw Zalando isn't, strictly, a Rocket company - it had a distinct set of actual founders) are now pretty desirable employers in their respective countries, and deliver relatively good customer service, certainly better than many much bigger and more resourced companies, and usually crushing the non-existent, overwhelmed service you can expect in most emerging markets. Is the backend a little messy and "move fast and break things", sure, but I was surprised by how BAD most backends actually were in the business world period, and the codebases I had a look into were, by those standards, alright (for example: enforcing foreign keys! a luxury in the Era of Mongo and "logic is in the ORM"). What about the warehouses? Perhaps not quite Amazon, but definitely a huge step up from the average e-commerce startup. At least you know where your inventory is, you're not somehow missing 3%.
Yes, Berlin can be a bit abrasive on egos. I left in part because of that, or at least it tipped me over the edge of setting up my own thing after dealing with one too many fake-angry German (hi H!). But with a bit of time and distance I really appreciate what the Samwers tried to do, and there's definitely a lot of founders who got their "change in life" thanks to a few months/years in a Rocket company, making their mistakes at someone else's expense.
It's also quite impressive that Oli is still as hands on as he is, very numbers driven despite flying continuously around the world, spending less than a day in each business yet knowing their numbers better than their managers. I think the tone of the email, and his motivational speeches, is taken out of context; also, the "vision" is, when you strip the hyperbole away (in Australia: "I do not want to be before the wave, or after the wave, I want to surf the wave"), relatively accurate. By modern and especially American standards, he's quite a polite fellow if demanding.