Icardi and Patrick Cutrone also saw strikes disallowed as the final whistle heralded a share of the spoils.
"It's a point earned, we risked going behind several times," Gattuso told Premium Sport at full time. "Inter deserved more, they made us suffer. We made too many mistakes, I'm happy with this point.
"In terms of quality we had to do better, this is a precious point because we risked losing. They've changed something tactically in the last few weeks and with these mechanisms they can cause problems for anyone.
"The best things we did were when we used the ball in the middle of the pitch. [Leonardo] Bonucci had to mark Icardi so he couldn't build the play that much. We got the final ball wrong at times, but I'm content with not conceding a goal against Inter."
The result keeps Milan sixth in the table, eight points adrift of the top four.