And even on this point, it's not all bad when you consider how design/architecture studios operate. I probably would've been better off as a junior dev if a bit more of my personal inventiveness (cough - ruby metaprogramming - cough) had been smacked down
Source: friend worked in his studio.
An important part of finding this balance is deciding exactly how much you trust your underlings to know enough about what the hell they're doing so that they don't do anything dumb, and to have a vision closely enough aligned with yours that their attempts at improving your ideas usually make you delighted. Clearly Sachs is not willing to extend much trust to people he is just now hiring to work in his studio.
Like, would you be happy with an intern fresh out of school who decided to roll their own crypto instead of interfacing to the library you told them to?
It's not a good situation but it's standard among big nane artists (Koons is notorious for strictness, afaicr)