I'm sure someone will be along to call it knee-jerk in a minute but for me there are quite a few issues (some of our own making) and I'm not sure any of them are particularly easy to solve.
Exhaustion - we've used much of the same core consistently for what, 4-5 years now? We've not always had great depth during that time and we've absolutely run some of these players into the ground, they just look like they have nothing physically left to give. So many key players from our recent successes look like they just do not have the legs for it anymore and we've failed to adequately refresh the side. This is concerning, because it doesn't feel immediately reversible and it's already apparent THREE games into the season - fuck knows what it's going to look like come Christmas when the games are coming thick and fast. It's actually a bit unfathomable to me where we are when the hallmarks of most Jurgen Klopp sides have been high-energy, high-pressing and high-intensity. Nowhere is that more apparent than midfield, where we don't have a single athlete or player who can press and cover consistently.
Complacency - some of these players don't look mentally right. Maybe it's the mental and physical exhaustion from playing so much football the past few years and so many near misses, but there have been plenty of performances that aren't good enough that date back to last season as well. Some of our world class players who are supposed to be in their physical primes are turning in lazy performances because they know they'll be picked every week. How many times now have we started slow and conceded first? How many half time threads read "shite, but Klopp will sort them out and we'll be better in the second half". Again, this doesn't feel like a particularly easy fix. Maybe it needs a run of wins, but mentally we look fragile at the moment and it's not often you can say that about a Klopp team.
Tactical stubborness - we almost never vary the way we play, even when we very demonstrably do NOT have the players available to play it. Why are we playing a high line with Nat Phillips? Or when we have no midfield (and no legs to put pressure on the ball)? Is it arrogance? Do we not practice alternative approaches? We're incredibly predictable and at the moment, incredibly easy to play against. Sit deep and sling long balls in behind Trent or through the gaping chasm that is our vacant midfield - you'll get joy eventually.
Strange squad building decisions - quite how we've let the midfield stagnate to this point... Why did we spend what appears to be the entire summer budget on Nunez when he looks, to be kind, like a massive project who is largely at odds with the way we play? He probably doesn't start when Jota is back and meanwhile we're struggling to put a functioning midfield out. We sold Neco who looks a competent PL fullback and replaced him with a young and inexperienced lad who by all accounts isn't ready to play for us yet while Trent looks absolutely goosed. The two most promising youngsters we've signed in recent years both look like they'd be most effective as #10s, a position we don't play with. Absent any contract renewals that are probably not deserved, we'll probably end up letting Wijnaldum, Origi, Milner, Keita, Ox and Firmino all go on frees (and let Mane go for frankly a pittance), when we're a club who tends to operate sell to buy.
I'm not even sure you can point to a single of these factors and think - yes, easily rectified. The set-up is maybe the most obvious one, without going into the transfer market which we clearly have no intention to do.
