My black and white comments are that the player is either on or offside, compared to other VAR decisions like fouls which are obviously more subjective.
Whilst I clearly don't doubt what you're saying and you're clearly knowledgable on the subject, that's a highly technical point. Whatever the technicalities are, once that's decided upon, the offside rule needs to alter and define what part of the body is considered offside.
Nobody's slagging VAR off due to co-ordinate triangularing and 50fps cameras, it's because a rule is being applied in conjunction with new technology when the rule was written without the technology in mind.