Yeah maybe that's a bit OTT given that we were always going to be top 5 with Arsenal's current demise.
However, we conceded 50, 48 and 50 during Rodgers' last two seasons and Klopp's first. Two most recent seasons it was down to 42, then 38 and now, although way too small a sample size, we've got the best defensive record in the league after six games. Given our defensive issues over the last half decade, I'll take that, and it shows that Klopp has improved us defensively, something he was unable to do according to lots on here. Not to mention he's doing it with a a very young back four that has immense room to improve.
Van Dijk was the missing piece in our defense, and if the recent trend is anything to go by we're only going to get better defensively over the course of the whole season, rather than the opposite (what you're claiming). We had already conceded more goals after one game last season than we have after six games right now.
(Not saying we will definitely not fall apart, but it's unlikely based on current stats and form imo)