You are mixing apples and oranges....................
But one volt will not cause one coulomb of positive charge flow across one ohm.
They need to change that standard to negative charge.
Ohm's and the other laws only apply to negative charge.
We do not flow positive charge. If we did, we would need new proportional equations.
Positive charge weights 2000 times that of negative charge.
If we did use positive charge............there would be a noticeable inertia and weight gain of circuit, with increase in current.
Positive charge, in the context of current flow, is an imaginary concept that has the same characteristics as the negatively charged electron except for the sign of the charge (rather like a positron). It's as valid a concept as imaginary numbers.
Thus Ohm's law applies and it's correct to say that a coulomb of (imaginary) positive charge is transferred across one ohm every second by one volt.
Please don't confuse things by referring to the positive charge of a proton (I assume that's what you mean when you say the positive charge weighs 2000 times the negative), which has nothing to do with this discussion.