Many tools hard code the "if windows then 'Scripts' else 'bin'" logic. They will simply fail to work with environments that don't have that layout. Yes, they probably should use sysconfig, but many don't (and sometimes for arguably good reasons, for example tools run using one Python interpreter that manipulate the environment of a different one).

It's something that *could* be changed, but the cost would be significant, the work needed to manage the transition is non-trivial, and the benefit isn't particularly obvious - "consistency" is never very compelling in isolation, and "works better with meson" is likely to be met with the argument that Python's layout has been around longer than meson, so it's on meson to accommodate Python, not the other way around.

I'm not actively against the idea, but neither do I particularly support it (I'm pretty sure it would require work for pip, for no benefit to pip's existing users, so it's a net loss for me personally).

If you're interested in pushing for this change go for it - I suspect that it would probably need a PEP, and at the very least it would need a community discussion - but be prepared for it to meet with a certain amount of resistance.