"In Italy, without written provisions, your family will NOT have access to your accounts if you have a stroke, fall into a coma, or lose your capacity. Banks block everything. Even your spouse. Even your children. Period." Any ideas what to do about this apart form getting a Procura generale notarile which costs €1100 (Italian notaries are the highest paid people in the country)

You could have separate bank accounts for example but at the end of the day most countries have a some sort of similar provision so the important thing is to understand exactly what you can and cannot do and what remedies are available so that you can have "power of attorney" in all the situations that life throws at you. So getting a power of attorney AND writing a will are things that should not be put off wherever you are living.

Suppose a couple have a joint account and the wife a personal account. In the event of the husband pre-deceasing the wife, she could move any money from the joint to her personal account before she informs the bank.
Doable perhaps, though maybe not an easy thing to remember at such a time.
(I agree that notaries are a rip-off.)

In my experience it is exactly that. Have a bank account in both names. If something happens most bank managers will allow you to move 50% of the sum deposited into 'your' account before freezing the joint account to wait for the succession. If its a stroke or incapacity, you can continue to use the accoutn as before as long as its 'one to sign'.