Differenciation in general is difficult to find everywhere. It would seem that everything is now created to satisfy and algorithm that makes everything out there, including casinos but also all websites, all videos and even movies look pretty much like each other. It is like the guy who said that if people want to buy Coke, I am not going to sell them Pepsi. It kills innovation.
Its not overacting but rather a common impression which even myself would really be having those kind of thinking and views about sites which does have the same vibe and design.
Copying is never been good.They might have able to have some changes or applications but its not something that you cant notice specially if you have seen this on the market for long.
I dont know on why copying is not something appealing in the eyes even if they do put up some additional games or changes but it cant really be removed on someones
mind that you have been copying others.