Chee was tarred by his NUS episode, more so if he wants only to portray himself as a torch bearer for social ideals, human rights, accountability etc. That episode was a bad starter. Then again later, he shot himself in the foot with his hunger strike and glucose sip. Knowing PAP, if you want to run for political office, you have to keep a squeaky clean closet and a impeccable moral slate, like Chiam, LTK and JBJ except that on the last, the Old Man had to clutch at straws to cast ambiguous aspersions on his magistrate time and his career stymie, and when they found that it didnt cut ice with the voters, they fixed him with lawsuits etc. which the voters can do nothing about.
In JBJ's case, people could see grave injustice and unfairness, and people empathise with him, even pity him, for they saw that the only thing he was doing was fight against injustice etc. But in CSJ's case, the people saw him coming across as a self-serving academic in NUS, and later on,he taking on the PAP as a personal vendetta. That is exactly the public image that the PAP wanted to etch on him, and they succeeded with control of SCM.
It would have helped imho if he had done things in those early days that would have ameliorated this image and regain voters' trust, such as helping residents with their appeals, problems, etc. to show that he was prepared to acknowledge his error and start a new leaf. And doing it facelessly, humbly, and pro bono, so as to build some powerbase for the future. But no. He staged a coup that ousted Chiam and then took on PAP full throttle and raised the ante by his court exam of the Old Man, and for many weeks, crowed about how uninvincible the Old Man was, and how he outwitted him in court.
I mean, Chee may be more brilliant academic than LKY but as a strategist and tactician, he is an infant. Politics is ugly, and unless you can also dream and scheme, have a Machiavellian streak, you wont succeed in politics. Merely being a goody two shoes will get you run over and crushed.