Hibs were pressing for a second half equaliser when goalscorer Ianis Hagi went into a challenge on Joe Newell inside the Rangers box with his boot raised high.
Stewart, who played for Hibs between 2005 and 2007 before going on to spend three years at city rivals Hearts, felt referee Willie Collum should have pointed to the spot.
"That is a penalty kick all day long," he said while analysing the incident on BBC Sportscene. “It’s dangerous play.”
Fellow Sportscene pundit and former Rangers winger Neil McCann was less convinced, however.
“The only reason he doesn’t give it, and I don’t believe it’s a penalty, because there’s no contact,” he said.
"But it’s a reckless challenge. It’s a crazy challenge to make.”
Hagi struck in the 33rd minute to seal a 1-0 win for Steven Gerrard's side.