Manager Malky Mackay has reportedly been told by owner Vincent Tan to resign or face the sack due to disagreements in areas such as player recruitment and performances.
The Scottish boss was also not present at the club's press conference on Friday, with assistant David Kerslake standing in.
Bruce, whose Hull side gained promotion to the top flight alongside Cardiff last season, believes Mackay can be proud of his work at the club but said he is not surprised by events at the Cardiff City Stadium.
"Nothing surprises me any more because of the way football has gone," he said.
"From the outside they should be really thanking Malky, he has done a wonderful job. He gets them up, and is making a fist of keeping them up but it's the industry we work in.
"We keep talking about it, at the most successful clubs, the one thing they all have is continuity.
"You can keep changing (manager) if you're Chelsea and have the players they have but even then they return to Jose (Mourinho) for some stability.
"I think we are going to deter people from coming into management, especially up-and-coming young ones, as managers simply do not get time now."
‘The pure simplicity of the way Slot has managed the squad is probably the biggest thing I could say about him. It’s not broken, so let’s get on with it’: Liverpool legend full of admiration for Jurgen Klopp's successor at Anfield
‘I trained at Spurs and thought they’d give me a chance. But I received a letter thanking me but saying they didn’t think I was good enough – I was gutted’: How Tottenham missed out on signing Wales legend John Toshack
