I already said why in the post you quoted...because adapting to a league is not the only factor in a player playing well. The Andy Cole example you brought up is obvious proof of that (because he was already adapted to the league having played there already, but still struggled) but you seemed to have twisted it to support what you said. Not once did I say that Keita doesn't need time to find his feet, I did however say that him coming from the Bundesliga is not a legit excuse.
Pep Guardiola said that the Bundesliga is an intense league, but the major difference is that the fixture schedule is congested in the PL (Keita has played barely any minutes, somewhere around 1000, nowhere near enough to say that he is fatigued).
http://www.espn.co.uk/football/manc...ague-not-more-intense-than-la-liga-bundesliga
The common difference between La Liga and the PL is the competitiveness, both Mourinho and Guardiola have said that the PL is harder to win for managers.
Seria A teams have a higher tactical requirement than the PL:
https://www.goal.com/en/news/10/ita...nho-serie-a-more-tactical-than-premier-league
I don't think I've ever heard a player from Germany say that the PL was too much for them to adapt to. Bundesliga has a good physical level with the main difference being money/player quality.