After being outed as a rat, Willie Boy Johnson was allowed to live up for 2 years before finally being hit, and he wasn't even killed by the Gambinos.

My question is, why was a known rat allowed to live as long as he was, especially since he was living right in the neighborhood?

Probably making sure the feds weren't watching anymore and let him think he's safe

revenge is a dish best served cold

Because they were giving him a false sense of security & it was contracted out- due to the heat it will bring

The same reason why john favara was killed months after frankie died. Gotti knew the fbi was watching him and waited until the heat died down. Both murders showed the ruthlessness of gotti and the mob. Ironically willie boy was involved in favaras murder as well as other murders

I guess it was for all the above reasons, and also Willie must have been really on guard. Maybe it took that long to get a shot at him.

Also John "forgave" Willie Boy. He told him that he was safe as long as he didn't testify and Willie bought it hook line and sinker. Willie was either very naïve or he thought his long friendship with Gotti meant he was safe. he didn't understand that gotti didn't care about anybody but himself. When Angelo was on his deathbed he refused to see him despite being like brothers.

Wasn't him leaving the truck from the Luftunsia heist double parked with his prints all over it the last straw? Or was that the "excuse" given for why he was hit? Or am I sounding like a dumb as and thinking of someone else?

^ That was Stacks that left the van behind while getting high with his bitch.