The Red Devils, along with the rest of England’s ‘big six’, withdrew from the ESL on Tuesday night as the competition crumbled just 48 hours after being announced.
But while all the Premier League sides have retracted their intention to join the breakaway league, Butt feels an apology to the fans will still not be sufficient.
Speaking to Sky Sports, he said: "I don't think an apology is too great anyway if I'm honest. I think what happened should never have happened.
"What happened is the worst case of bullying in my opinion, from powerful people, so whether they apologise or not is irrelevant to me really."
Butt, 46, who played for Man Utd for 12 years between 1992 and 2004, returned to Old Trafford eight years after departing as a player to begin his coaching career.
And after various roles with the English giants’ reserve and academy sides, he announced last month that he would be leaving once more.
As a result, the distance he now has between himself and the club allowed him to be frank and candid about his ex-employees controversial decision to join the Super League.
When asked how long it will take for the Man Utd owners - the Glazers - to regain the trust of the fans, he added: "A hell of a long time and I don't see how it's possible. It's difficult to regain someone's trust after going behind people's backs for so long.
"It's going to be difficult, I don't know how they do it. I think that's how some of these businessmen work. They work in the shadows if you like and they do what they think is right, but I think the shocking thing is they can't have empathy for the fans who make this sport so great.
"Without the fans, the sport is nothing, and to not be on board with what the fans want, that's the alarming thing for me.
"So it's a lesson to people who come into the country and come into powerful football clubs and think they can do whatever they want because they are owners and they are very, very wealthy.
"Over the past few hours in this country it has proved not to be the case."
Man Utd’s first game since the ESL announcement will come away at Leeds United on Sunday afternoon.
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