Many IT folks were cocky during the post-COVID height. Some even mock Unions for making firings harder, worried that their "incompetent" co-workers difficult to boot.
I've known of two engineers whose managers told me they would have fired them, but higher management wouldn't let them initiate the PIP process. The one case where I worked at the company was pretty bad. We had to shuffle the individual off onto makework jobs where they couldn't do much harm.
I don't think it's fair to blame this entirely on unions when it's the result of big businesses being too scared to follow a process that was given to them by the government. Unions mostly fight real unfair dismissals and only play a minor role in creating a chilling effect. Still, in practice it's hard to fire someone.