Italian coaches are prestigious around Europe, it is one of the premier coaching schools. The recycling of experienced coaches is to be expected as they don't see the necessity to go abroad as they believe their coaches are up there with the best. English managers in comparison are few and far between, or not seen as good as foreign coaches, so their clubs will inevitably sign whichever foreign coach whose stock is high and in demand. They have the opposite problem to Italy. I also think it's much easier to transplant a Dutch coach into English football, for various reasons. And then you've got the issue that the best foreign coaches will want to go to England or Spain ahead of Italy. Serie A is full of the experienced Italians and those cutting their teeth.
Roma have tried a mix of Italians, foreign coaches from calcio, and external, the latter of which all failed. Inter's foreign coaches during Moratti's era all failed bar post-Farsopoli Mourinho. Milan have tried two Portuguese coaches in a row and both failed. You can see why they revert to their "safe mode". But it's quite a small sample, and obviously many more Italians have also failed in the past 30 years.
I like the idea of a foreign coach coming in and at least trying to get us to play in a completely different way, but I'd also be fully prepared for it to be something that might take 2-3 seasons to come to fruition. If the club is at risk of missing top 4 in any season they'll invariably replace the coach so this'll never happen. It's a shitcycle.