not just the members states but also all the other behemoths stakeholders like Airbus, Thales, OHB and so on, which need to make sure that new missions are as easy to adapt to their preexisting flight heritage as possible

A bureaucrat is not allowed to spend money on anything risky and must never allow for money to be used on something other than the intended use.

So the entire process must be micromanaged to death with documentation, which results in the money mostly being spent on the documentation.