The league means consistency and nothing out of the ordinary, no sparkle, on the other hand, the UCL means intensity, value, potential, when I think about the league/UCL ratio, I think of that Barcelona of 17/18 that was very consistent in the Copa del Rey or the league with weaker opponents, but in the UCL, it did not present any high-level potential or intensity, very weak from many points of view.
I know that many people will say about 11/12 or 20/21 Chelsea being the weakest possible UCL winners, but guess what mate, defense is also part of the game, if a team prefers to defend in a 4-2-3-1 or 3-5-2, it is their choice to do so.
Nobody will say about Real Madrid 2016-18, that they only won one title and no domestic cup and that they are a weak team because of that, absolutely not, many say that they are in the top 5 best teams in modern history.
Just like you can't say that Barcelona from 2016-21, simply has bad luck and that's it in the UCL, no bro, they were extremely weak and that's it, nothing more than that. As Thomas Muller said, "they can't cope with high intensity and stressful games".