I suspect you're getting confused with 2022 - Collingwood had the best percentage in the league in 2023, despite playing a handful of dead rubbers late in the season.For sure.
But last year they weren't incredible. They literally were a goal or two difference every week (including finals and the GF) between being a good team and an average one. They fell over the line on a weekly basis.
A slight drop off, of even 2 or 3% would have made a significant difference to their season. And I think they have dropped off this year. Not heaps, but enough to not be able to carry the bad lapses they had during games last season.
It's not as if they were a dominant force that were 10 goals better than everyone else.
I guess it's easy to get confused between seasons when a certain team is a regular contender.