The thing is that the top teams in most leagues are rather stable and can plan on playing international football (and reaping the corresponding revenue and prize money) every season, so that they can afford to build large squads geared toward playing in 3/4 competitions. On the #6 or #7 spots, there is typically far higher volatility from year to year, so these clubs neither have the large squad, nor can they build one based on a one-off participation in international competition.
This. Their position in the Bundesliga, with its revenue stream and attractiveness to young prospects who can then be sold on for a profit, has become more or less self-sustaining. So you still have a lifeless village club without history or fan culture taking up a spot in the top flight while massive clubs like Schalke or HSV are stuck in the 2nd league. Hoffenheim would never have gotten above Regionalliga level (fourth tier) without Hopp’s money, so the damage is already done, even if he divests now.