Linear acceleration is equivalent to gravity. Spinning is not; it introduces the Coriolis psuedo-force or however you prefer to look at it, which allows it to be distinguished from gravity.

I concede the point, but counter with the fact that completely flat gravitational fields are implausible, so you could technically distinguish between linear acceleration (which has the same acceleration everywhere) and acceleration due to gravity (which doesn't, and hence generates a tide).

The effect on a stationary point sized object is equivalent in all three cases. When your object moves then the spinning artificial gravity can be distinguished. When your object is no longer point sized then both gravity and spinning fake gravity can be distinguished from linear acceleration fake gravity.

I concede you have out-pedantic'd me. :)

Not sure how this supports or refutes GP claim ...

EDIT I mean - we’re talking about convection right? Which I understand to involve circulation of air currents ... does your link have anything on this topic? I guess with a large enough centrifuge there might be no difference but it was unclear whether what was being referred to was large habitable centrifuges or the type more commonly found in labs ...