So lets not create a narrative that only players from countries that are not part of big 3 will be reported.
Few decades back when there were no good fast bowler and West Indies were in strong position they banned more than one bouncer which hurt them very badly and then have many rules for stopping them, and they were completely successful in this case after this they have illegal action rules for countries like Pakistan and Sri Lanka now most of the rules in test and other formats are favouring batsmen which is really poor by them.
I think these rules were made because at that time only a few countries had really good fast bowlers who were able to Bounce the ball and the top three countries were really afraid of them. And that's why the rules were being made to favor the batsman instead of the bowlers.
But I think the rules are ok to be made like this because it is true that otherwise there will be not many runs and people are not going to enjoy Cricket like they are. It is really rare to see the bowlers from the top three get any punishment.