"Stickler for the rules" my ass. Chin feared Gotti for one reason: because of the precedent Gotti killing Castellano set. It meant no one was bulletproof or above being killed. If Castellano got it, it might also be open season on the Chin. That's it.
Gigante obviously could not have been too much of a "stickler for the rules," considering that he tried to knock-off (and ultimately forced into retirement) Costello three decades earlier. Which is to say, the "precedent" was set by Gigante and Genovese, except that this was preceded by Anastasia bumping-off the Mangano brothers, which was preceded by Luciano eliminating Masseria and Maranzano, and so on ad infinitum
