It absolutely ruins the game. It's not just about what happened with Chellini which was more of a one off, but it enables an entire tactical strategy that teams like City (they aren't the only offenders) employ; play a high line / high risk pressing approach and if you get broken down and face a dangerous counter attack, oh well, just make a cynical foul and start again. It's such an advantage to those teams that have better technical players and have to face next to zero consequences when they get exposed. A yellow just isn't enough. Lower level teams, that may be the only good chance they get all match and it is undeservedly taken away because a team is caught out of position due to a high risk type tactic.
I'm actually fine with a red card honestly. Overall I do believe a red is harsh, but I really do believe this type of cynical approach ruins matches, so I'm all for cleaning this behavior up. I get the argument that a red in this circumstance also may ruin the match, but I don't care as I think if that was enforced in such a manner, you'd see it stop real quick. Also, it's not heat of the moment type of foul or moment of madness or whatever, it's a deliberate, thought out and intentional act to stop a counter attack. They know exactly what they are doing, can easily choose not to do it if they know the consequence is harsh, and well, if you commit the foul, see ya in 2 games.
A more reasonable approach would be to implement the sin bin / penalty box concept. Give a yellow, but the offender off the pitch for 15 mins. Then some sort of accumulation similar to overall yellow accumulation, but specific for this type of foul. Every second time you do it, miss the next match.