You will never convince me that Fresno St. was the best college baseball team in 2008. Will not happen.
Well as you said earlier it depends on how one defines the "best".
I do believe every team that wins it all is the best because they had enough talent, and
executed well enough when required, to do the things necessary to win a championship.
That does NOT mean they were the most talented
team, and frequently more talented teams do not win it all. But a more talented team's inability to execute with their superior talent shows they were lacking in a quality required to be a champion, so they were not the best.
If a team with the hardware is arguably not the best, then a team without it has even less of a claim to that title.