Not quite right.
I'm saying that the referee's interpretation of the law was correct.
Exactly. Whether there is another valid interpretation which would contradict the one given is irrelevant, as long as the one given is itself a valid interpretation.
I'm arguing against people saying that the interpretation was incorrect, not that it is/was the only correct interpretation.
I think the laws need clarifying but then they always do, as people find ever smaller loopholes. The problem in this case, to my mind, is that the laws have been slowly amended to cater for the introduction of VAR.
VAR deals in absolutes so Rashford can only be onside or offside due to his own actions. Not the actions or decisions made by other players.
Your definitions mainly. And then the fact you ignore the actual laws in your summing up; preferring your own versions - which sound quite sensible, by the way...