After being benched for the FA Cup final defeat against Crystal Palace on Saturday, it's been suggested Grealish will leave City at the end of the season.
Given told BBC Sport: "I have a soft spot for Jack Grealish and the way he is being treated is not on.
"He's not helped himself at times but he is a generational talent that you want to build your team around.
"That's back-to-back FA Cup finals where you need a goal and you don't use him. At the weekend City brought on Claudio Echeverri who made his debut instead."
Writing is on the wall
Given also said, "Jack is an international, a multiple winner, it was criminal he didn't get on the pitch. The writing is on the wall. I don't know why Pep even brought him to London. He may as well have stayed at home.
"When he plays, he's a mannequin on the wing and just told to keep the shape. Kevin de Bruyne is leaving in the summer and Jack Grealish is the perfect replacement to play in the middle but after what has happened, he maybe won't play for the club again.
"For his career, he has to see what is out there. He is an amazing talent with plenty of years left in him."