I understand your post It's hard to play in a tournament that you just know you can't win, so you want to change the tournament where the playing field is more level. The way I see it, though, is that the Cup is that part of BB that gives your team an opportunity to play outside of the regular league competition. For the top teams, it means that unless they randomly get assigned another top team in an early round, these games are easy wins and quick paychecks for their team, and also an opportunity to get in some training for younger players while getting their team Enthusiasm up. For the lower division teams, it usually means getting thumped in the first few rounds, depending on how lucky they are in getting matchups against similarly lower division teams.
Personally, I think if the tournament only featured games against teams in the same division, it would be boring. What's the point of a tournament that's just an elimination version of what I'm already doing in my league games? I see the Cup as an opportunity to distinguish my team and try to get ahead of the teams in my league. When my team is still playing, it's a challenge balancing the need to win league games and desire to grab those Cup win payments an increasing my Fan Survey. If I get knocked out, I look to see if I can get in edge in league games by not having to save my best players for a Cup game, and I also get an extra game where I can play my players out of position for training purposes without worrying about the outcome of the game. When I was still a lower division team, playing against better teams gave me an opportunity to really see what my team could do, and very often a higher division team would expect my team to roll over and not even try, so I scored a few Cup upsets that way.
I think every manager needs to set a goal, whether it's focus on league games or Cup games. It's really hard to do both, and that's just part of the game. I always set a goal for a minimum number of Cup wins and that usually satisfies me to try to reach that so I can make sure I don't kill my Fan Survey with an early exit (I failed badly this season!), and after that I'd rather lose so that I can make sure I reach season training goals, too. But that's my strategy and accomplishes what I like. Everyone needs to make their own assessment of how to approach the Cup, whether they want to win Cup games or could care less.
Don't ask what sort of Chunks they are, you probably don't want to know. Blowing Chunks since Season 4!