This is a very good summary for me. Yesterday was terrible, from start to finish, there's no denying that. Worst result & performance by far that I've seen under Arteta, by far.
Totally agree about the system as well, it's set up to be more solid & difficult to beat, & it works to a certain extent away from home. But it still has flaws attacking wise, & that's our major weakness. It's not working at all when we have to take the game to teams at home.
Our attack just doesn't function. Lacazette is not good enough to be a modern number 9 now. He's not physical enough, you can't play off him, he struggles to hold it up, the ball constantly bounces off him. Now, he's also not dynamic enough either. Ollie Watkins showed him how to play that role perfectly yesterday. The likes of Calvert-Lewin play it well. In fact, I'd probably take at least half the leagues number 9's to play that type of role over him. Probably more.
This is then compounded, when you have little creativity & play your main goalscorer out wide. The short term answer is surely to drop him & get Auba through the middle. Try & get more creativity around him, change to a 433 / 4231 variation to allow that to happen.
Bottom line is likely to be though, until we get more players in that have the skill set to play like he wants, we'll continue to stutter. I'm sure he'd have loved £250m this summer to try & fix all our problems in 1 window, but unfortunately not everyone gets that.