Ranieri was replaced by youth team boss Andrea Stramaccioni.
"Inter have been struggling for a while and the results were not arriving," Mazzola, a former player and director at the club, told TMW.
"You would have to be inside the club to understand what went wrong, but I would have waited before coming to the conclusion to dismiss Ranieri.
"I don't think the Coach is totally to blame."
The San Siro giants have taken the brave step to appoint Stramaccioni - a 36-year-old who will actually have three squad members who are older than him.
"I don't know him as a person so I won't allow myself to judge him," the 69-year-old continued. "Obviously you can look at his results which have been excellent.
"If he says the right things then the squad should follow him, but it depends how he comes across."