Yes many of the things I listed are just as easy to track with WFH, and even before WFH online interactions were a significant part of those. It is the showing up, putting the hours, and not wasting too much time part that is hard to track remotely.
If someone is making a reasonable number and quality of commits, fixing bugs, and communicating reasonably with their colleagues, does it matter if they're "showing up, putting in the hours, and not wasting too much time"?
With on-site (and open-office even more so), it was much easier to differentiate these two. I don't want to give someone a luke-warm performance review because their work was taking longer, when in reality they were solving harder problems. I also don't want to push things like pair-programing on someone who really doesn't like it (and I assume it is worse over Teams or what not than in person).
If you have an employee who is producing very little work, you're face with a decision about whether to put in a ton of effort to try to turn the situation around or put a ton of effort into firing them and hiring a replacement.
If you know the person has been showing up and doing normal office stuff that's a huge signal in favor of "this person is making a genuine effort so I need to go the extra mile on my end." It's harder to get that kind of signal remotely.
This isn't to suggest remote work is wrong. It's just that, for managers, dealing with these kind of situations was a big part of the job and now has gotten much harder.
Treat your employees/subordinates/colleagues like they're responsible adults, and they're more likely to act like it. That means, among other things, talking to them when you notice something that seems off, rather than just thinking it's your job as the Big Important Manager to solve all problems in your own head.
Treat them like they're bad children, or like they're all constantly looking for every way possible to get more money for less work, and you're more likely to get disinterested, frustrated, and rebellious employees. There's nothing more likely to make someone act like a child than treating them like one.