What on earth are you talking about?
Klopp called the fixture congestion madness. Mourinho called for the league cup to be scrapped to ease the fixtures, the big cheese at City said exactly the same. Can't be sure if Pochettino said similar but he probably did. Those at the top with better players have done well except Arsenal. (Wenger probably feels the same as the above). Not the sole reason for our slump of course, but saying others in Europe are not bothered by the fixtures means you need to read a bit more widely.
Do you really believe that 1 league cup game against a poor Sunderland team a month back is having a bearing on our form?