Agreed. But I don’t know of any mechanism to do this short of standardising, and the point of letting backends come up with something is so that they can iterate on the best solution - which means standardising prematurely is not the right approach.
But I’m a strong +1 on backend developers co-operating on a solution (which could then be standardised if appropriate). Maybe use a shared pyproject.toml section, such as [tool.shared] for this?