You also created naff all. There's a link between that, and Lampard clearly set up with a more defensive structure. You aren't going to be bagging for fun and keeping clean sheets just because Mendy has come in. People point to VVD and Alisson at Liverpool (who are obviously far better than Mendy and Silva, but that's besides the point), and how they transformed Liverpool's defence, but seem to forget the change in approach Klopp made when Buvac left, and how less 'gung ho' they were.
I have no doubt Mendy will help, but this suggestion that Chelsea's defence is good and it's all on Kepa is laughable.
How Chelsea should be judged will change every week. Whole last season it was "Lampard didn't sign anyone" even though few were added to the squad.
This season "we have signed too many players, so shouldn't be judged quickly" but the same "Signed too many players" isn't even applied consistently.
Thaigo Silva played and even made mistake vs West Brom but it won't count as Zouma wasn't next to him.
Zouma and Chilwell played vs Southampton but it won't count as Thiago Silva didn't play.
They should be judged only when Thiago Silva, Chilwell, Mendy, Zouma plays together and somehow "we signed too many players so it's too quick to judge" goes out of window if you get the results you were hoping for even if it's ridiculously small sample size. Good for James that they got clean sheet vs Sevilla, otherwise he would have been blamed as he was the only one who didnt play vs Palace.
Also going by these examples, Werner and Havertz is a piss poor combination, they signed 0 goals when they started together (In PL, didn't check, might be true for all competitions too). They are only good when Pulisic is added to the duo.
But then you always see some hilarious posts (which is expected at least one of them is just dumb, only line of argument is "What about ManUtd") and ever moving goal posts on how a team should be judged. Whole last season the excuse was "Our best CB is injured", now that best CB is a deadwood and was never good enough.
Edit: Btw IMO they will improve defensively, they can't get any worse than last season. 54 goals conceded is very poor record, they will improve on that easily.