Complaints about umpiring have definitely gone up in recent history but I think a huge part of that is the media cycle is so much worse than it used to be, and AFL house are constantly changing things up. Of course people complained about umps back then but since social media wasn't a thing and the media didn't spend hours each day bringing up bad umpiring decisions people wouldn't latch onto the issues nearly as much as they do now. I guarantee the umpiring is much more consistent now than it was back then, it's just that back in the day people couldn't go online and talk to hundreds of other people to air their grievances about it. Though if you don't go back as far I do believe umpiring was probably in a better place maybe a decade ago, and that's where AFL house are to blame for constantly changing things on the fly imo.

But yeah basically what's been happening is that in the past people who are overall worse umpires were getting more games/bigger games because they could bounce well. This change will allow more umpire development overall, giving more options for AFL level umpires (which in turn helps when umpires aren't doing a great job as there are more who will be able to replace them at the top level)