Yeah he turned out to be a rat, but the whole situation may not have even been an issue if Sammy had been Boss, because:

1) Sammy was low key. Like a lot of the best old school guys, Sammy kept himself low key and out of the limelight. Compare Gotti and Sammy's mugshots from their 1990 arrest. Gotti is all smiles, decked out in an expensive suit. Sammy is stone faced and dressed casual, like any 1990 era Bensonhurst guy. Who would guess was the Mob boss?

2) Sammy knew how to leverage both white and blue collar crime. Unlike Gotti, who was totally a blue collar guy, Sammy had interests in both worlds.

3) He wasn't a hot head. Sammy was a vicious guy, but he wasn't an impulsive hot head who made decisions without thinking, whereas Gotti was loud, in your face and very impulsive--and even was dumb enough to threaten people over the phone or talk about guys who were whacked.

4) He knew how important legitimate income was. Sammy had several legitimate lines of income to insulate himself from the Feds, and he also lived within his means. Compare that to John, who claimed to be nothing more than a Plumber who wore $2000 suits.

I just think Sammy might've been an improved, more street wise version of Castellano if he'd been Boss. Have a family with Sammy as Boss and Frank DeCiccio as Underboss, with Gotti as a Capo and things might've worked out into the '90s.