I do think one thing that helps england is that some of the plyers have amazing managers to develop under. You've got Mourinho, Ancelotti, Guardiola, Klopp, etc, all developing players. It's quite well known how Sterling has developed him (Regressing a bit this season, albeit), Klopp has done an amazing job with Henderson for example. Italy has a real lack of managers who have developed players properly IMHO - Conte was great for it, I'd say the Sass manager who has now left obviously did well too, Gasperini ish (very good at making them work in a system, developed some players well, but obviously Gagliardini, conti, caldara, etc, have struggled when moving)... Allegri coming back to Juve should help, IMHO, much more so than Sarri/Pirlo.
I dont know if Shaw has developed under OGS or if its more Southgate's influence, but he's streets ahead of where he was a couple of years ago, for example.