The chances are increasing according to both Greg Bedard of the Boston Sports Journal (subscription required but recommended) and a “Bill Belichick-friendly source”:
“A Bill Belichick-friendly source agreed with my thinking that once a player makes Belichick start to contemplate life without him, Belichick starts to warm to being without that player. “He imagines you gone,” he said. The longer Gronkowski goes without saying he’s all in, the chances of him being traded increases, the source said.
Bedard added “everyone” is in an agreement that a reunion with Jimmy Garoppolo in San Francisco is the most likely scenario for Gronkowski as maybe a makeup for robbing the Patriots in the trade for Garoppolo. The Rams were also floated.
Given that Bedard is especially plugged in with Belichick’s way of thinking, Gronk seems to be tiring of the shackles in New England and Bill Belichick’s proclivity to move on from players, it would not be astonishing if Gronk is traded soon.