The answer is quite simple to be honest, and if you're choosing to shirk a decent sized portion of the blame onto Ruben then I'm afraid that you are a part of the problem with this club, and you are actively contributing to the perpetual cycle of poor attitude that has reeked the club out for the past decade. The fault lies with the players, simple.
I strongly suggest that some of you take off the tinted glasses for just a moment and judge our players on their technical 'abilities' and how they carry out (or attempt to) the basics of football. 80%+ of them struggle to carry out a simple 6 yard pass a majority of the time. The Leicester game showed this on many occasions with Amad running down the wing and producing the most lacklustre 1-2 attempt with Mainoo, with both of them failing to find each other in tight spaces MULTIPLE times. It's fine for it to happen the once, but this happened 3/4/5 times... and Amad has been one of better players of late, and that's my point.
The squad overall is NOT good enough. I've said this before and I'll say it again. Out of the teams above us in the league, I'd have every single SQUAD of players other than Palace. If you take off the tinted glasses, you'll see it too. If you don't want to see it, that's fine, we're all entitled to opinions, but just know that this sub standard of football will not improve until the fans accept that the players are not good enough bar Bruno, Ugarte, MdL & Mazra.
Ruben picks the formation, the line-up, playstyle, tactics, instructions etc but he isn't the person that's physically tasked with carrying them out is he? The players are, and they can't do it because they lack the ability to do so. Other than the players I've mentioned above, the rest of our team would not get into the Villa squad for example, or Fulham, Newcastle, Brighton.... it's endless.
The clear out began last summer and is continuing to do so with Rashford, Sancho, Malacia & Antony all on their way out, so the baby steps have started, but we have a LONG way to go, so we need to buckle up, take off the tinted glasses, and get rid of the Player FC mentality that is so strong in this fan base, so we can return to our former glory days.