>>26974800>Cont.One plays top tier deck is not EXACTLY the same as another's, but they both follow the same strategy and same staple cards that are required to win. Now apply that to VGC and the staple cards become the pokemon you use and, more specifically, their stats and movepools.
Pokemon changed the rules this year in, what appears to be, an attempt to diversify the meta. This barely made a difference, as the new available pokemon became the new standard best options, and of that list, there are a select few that work the best.
As in any game, there is always going to be that one combination, with slight variations, that is the best and does what players want it to do: WIN
There are a few occurrences where counter-meta teams take first place. This wouldn't be possible without the meta being the way it is in the first place, they rarely win against teams they don't specifically prepare for.
>TLDRThe VGC top teams will never not include the same basic team setup because players know what wins the most.