It's a chicken and egg situation. 99% of the time, players like Suarez and Neymar go down as if they have lost a limb. The referees are right to err on the side of not buying their bullshit. How many times have you seen players get carded for less against Iniesta for example? Suarez is the absolute worst. He doesn't even get fouled often and goes down clutching his face it's INFURIATING.
Having said that, I think referees should be more proactive and call fouls/yellows/reds when players are genuine. For example - when Messi gets hacked away game after game after game, he ONLY gets a yellow after many such challenges, and ONLY after he goes down. ALL those shitty challenges that he just rides or doesn't make a meal of, they go unpunished by the referee. Neymar fanboys will make the argument that that's the reason he dives, but there's a middle ground. You don't have to be like Messi (because not many people have the skill to do what he does riding the challenges) but clutching your legs as if they've been chainsawed off doesn't serve any purpose, and referees will obviously be more cynical.