This is not "from Italy", it's been organized by a far-left Italian magazine. Yes, they are "from Italy", but the title is disingenuous and misleading.

Note that the page lists "the editors" (of the magazine) as the authors, and the first signature is by the magazine's publisher. The rest appear to be various academic personalities they have reached out to, many of them not from Italy or in Italy.

As for the contents, I don't necessarily disagree with the advice, but this letter is not particularly well written, nor particularly authoritative.

For example, this section:

> The beginning of the outbreak had the exact same number of infections in China, Italy, and other countries. The difference is that China strongly and quickly locked down Wuhan and all of the Hubei region 8 days before Italy [3].

This is an exceedingly poor phrasing, almost seeming to suggest that the outbreak started with a few cases everywhere in the world at the same time. Inadvertently or not, this dovetails with China's PR push trying to claim that the epidemic may not have started there (something that is readily disproven by all epidemiological and genetic evidence).

Even setting aside the potential for confusion, the claim on its face is clearly baseless. Maybe the outbreak started with ten people getting infected in the Wuhan wet market on the same day (if we go by the wet market theory), while in Italy it started with a single infected person entering the country. Or, vice versa, maybe in China it started from a single infected person, and in Italy it was brought in by ten different people carrying it into the country separately. Who's to say?

At any rate, if you look at the source for that claim, you can see that it is shifting the timelines to align at some particular point in the outbreak, and it is comparing the time from that point when China imposed the Wuhan lockdown with the time when Italy imposed the whole-country lockdown.

The source is certainly more interesting, and gives a better picture of the situation than the letter does (although we have seen similar and better analyses in English for a while). However, the "8 days" figure is somewhat arbitrary. For example, Italy imposed a partial lockdown on the areas of the country where individual cases were found days before they shifted to a whole-country lockdown. Maybe that date should have been compared instead?

By the best information currently available, the first case in Italy came from a person who was infected in Germany. According to the letter's claim, the outbreak starts with "the exact same number of infections" (one, presumably), and then grows at the same speed. But then Germany's timeline should be ahead of Italy, yet it's not.

Then there is the elephant in the room, of course. If you cannot rely on China's lockdown to contain the infection, then the rational and prudent thing to do was not to wait for outbreaks in other countries and impose lockdowns there. It was to restrict and heavily control international travel (cancel flights, test all passengers, force visitors to quarantine, etc.). Would that have been accepted by the public? Would that have been accepted by the authors of this letter?

tl;dr: title is grossly misleading, please correct.