Fair enough. In which case, would you say that Arsenal, Man City, Man Utd and Leicester have defences that are more suited to Europe than we do?
Or for example, do Genk have a better defence than Gent?
I think you're putting too much stall in one off cup competitions tbh. Yes Man City went further than Arsenal last season in the CL. Yet this season, they just reached the same stage? So did their experience change so drastically in one season or Man City's defence became less suited to Europe etc?
Its worth remembering I think the difficulty pretty much all the English clubs have had in their first attempts at the CL.
I mean, Ferguson's record early on in his Man Utd career reads like this: Knocked out in the 1st round of the UEFA cup by Torpedo Moscow. Knocked out in the Champions league second round (ie before the Group stage) by Galatasary. Finished 3rd in the group stage behind Goteburg and Barcelona in the CL. Knocked out in the UEFA cup 1st round by Rotor Volgograd. Then finally, 5 years into his forays into proper European football as a Man Utd manager, reached the CL semi final.
These things take time, experience, mentality and also definitely the right players too. We are still on that journey and I don't think this season's performances and results can be explained by any one factor or are that unusual for English clubs in Europe.