I think it's easy to understand
It's just an ego-centric position to take (and, to be clear, it isn't mine).
I think it goes: "I'm a fan. I like watching ND win. ND has a far better chance of winning a NY6 bowl than a playoff game. (Probably add: A NY6 bowl still carries some weight, at least moreso than any other non-playoff game.) Ergo, I'd rather ND play a NY6 bowl."
It ignores a great deal of other factors, including the benefit to the team/recruiting of consistently being one of the top 4 teams when the playoffs start. It might also be easier to hope for this year since we weren't expecting to contend this year and we have almost no chance of making the playoff even if we win out, unless there's at least 1 more week of pure chaos (that doesn't include us), and maybe two.
However, it all strikes me as pretty meaningless b/c obviously BK is doing whatever he thinks will get us to the playoff. He knows better than anyone that the one thing that's keeping him out of the "best ND coaches of all time" discussion is a title and the only way to get one is to make the playoff. I'm sure he also knows that this is probably the weakest field he'll see in his remaining years (though also not the strongest ND team). So fans can hope for or "settle for" whatever they want, but ND is going to try to win all its games and hope for chaos so it can make the playoff.
All of which is to say, Kelly would love to win every game by 50. But he'd much rather win each of the last 3 games, than beat Navy by 50 and risk more injuries/depleted health. Given that we might finish the year with 8 "healthy" players and 3 student managers starting on defense, I say let him do whatever he thinks he needs to do to win. Style quickly becomes irrelevant if we don't win out.