As an employee with Federal and working from home I can confirm that any talk that productivity or delays as result of working away from the office is 100% full of poop. It's propaganda because of the pressure that Ottawa (and other) downtowns are facing from the local businesses who are complaining that business is down because the federal employees are the ones buying coffee and lunches from them.
I've worked at 4 different federal gov't agencies in my career and I know first hand that people are far more likely to not work a full 8 hour day, take excessive breaks, get distracted with conversating with fellow employees when in the office. Also the mental health aspect is a huge factor, not having to spend 1.5 hours per day in my car rushing to get home to pick up my kids from an after school program is a massive benefit.
I also know people who work with the provincial justice system, they were back logged prior to COVID because the sheer amount of crimes in Manitoba is incredibly high. That number of crimes sky rocketed once people were locked at home and drinking more and whatever other factors that lead to people committing crimes. Most of the provincial staff had to work in office because the system is antiquated and still uses a lot of paper.
I'm not sure where Lawler falls in but it has nothing to do with WFH or Hybrid.
Unions do protect bad employees, but what you are complaining about is a management issue. I've seen people completely hide behind the union and do absolutely no work, but it's not like these people once in the office work hard and then at home stop. These folks won't work no matter where they are and who they work under.