But when you look at the roster differences, let me put it this way, the roster value of France is 1 billion euros, the same for England? 1.1 billion, now lets take a look at how much Croatia roster worths; 360 million. You can say whatever you want to say for the reason of it, it's just not the same and will never be the same at all.
This is a strange argument. England and France are home to some of the richest football clubs in this planet and therefore the local players can expect to get good contracts. Croatian players on the other hand doesn't get noticed by these clubs very often. Around half of them play for Croatian clubs, such as Dinamo Zagreb. But that doesn't mean that these players are inferior when compared to players from England or France. And the contract values are not purely based on performance. Fan following also plays its part. England players can demand a higher contract value, since their fanbase is larger.
Imagine saying that players who play for Dinamo Zagreb could be better than players who are playing for City or PSG, does that make sense to you? If they were that good, then they would have been at big clubs as well, look at Modric, he is the sole winner of Ballon D'or during the period Messi and Ronaldo dominated the award, was he a bad player? Was he just at local league? Of course not, he was dominating the world at Real Madrid at that time and that is why he won.
So all in all, I can easily say that playing for the domestic league is not a good answer, not all English clubs have English players only, and not all French ones have French players, they hire players from other nations and if Croatia was any good, they would be valued a lot higher and be bought by huge clubs. It is as valid argument as it gets.