You're really understating the expectations, particularly at Liverpool, which is an extremely high pressure environment due to the expectations (and previous desperation) of the fans combined with the more limited budget. These aren't clubs where you aren't expected to win, they're clubs where you're expected to build a winning team within a few seasons. That's more difficult than inheriting the best team around, and are expected to continue being the best, although that isn't easy in itself.
You're right that many coaches struggle at top teams, I've said repeatedly in this thread that there's a real skill in being able to take the best team and make them look like it, especially keeping it up consistently, and Guardiola is a master of it, at least from a league point of view. However, I still rate Klopp's achievements higher, as he's done it in the with the underdogs, retaining the league with Dortmund and taking Liverpool from a bit of a joke to a dominant powerhouse.