1) China has not been honest, in the least. They have made errors upon errors and probably kept both the numbers of infected people and the number of deats lower than they really are.
HOWEVER, China's situation was as clear as day when they imposed the Wuhan quarantine, on January 23rd. That was when it was CLEAR that sh*t was hitting the fan, and everyone else should have prepared accordingly.
Unfortunately, almost none did it, becasue they were afraid of losing their economy, an economy COMPLETELY UNPREPARED for such a situation. They all kept clinging to a sunk cost, and now we are all paying much more than needed.
2) Yes, companies ARE ALSO bad, in this. This pandemic has shown the MASSIVE shortcomings of the current (probably past, at this point) world economic and social systems, by hitting its weakest parts. The companies who are helping now (many of them genuinely) are the same companies that helped the situation get to this point of unpreparedness, so they are not going out of their way: this is part of the Enterprise Risk. You are not going to get filthy rich without risking anything, are you?
Many countries made similar mistakes:
a)Worshipping money and the rich
b)Maximizing short-term profit and reducing the resilience of the system to unexpected problems
c)Thinking that, somehow, everything could be solved through money
d)Losing sight of all real values that were not "wealth" and giving power to incompetent, unprepared, short-sighted people
e)favouring short-sighted, selfish, avid mindsets in people
But I think Oliver said it better, and although he is speaking of the US, most of what is said can be applied to anyone) (if you don't want to watch it full, which I recommend nonetheless, start at 17:15)
As this seemed to granting wealth and more wealth, now its shortcomings are hurting everyone.
3)Other countries
China was by no mean good or honest, but it's not like everyone else is saint.
Most countries are downplaying their deaths (Germany, France, Iran?) or their active cases (China, Russia, UK, Iran?), or both.
Many countries don't have many cases simply because they aren't testing people.
Link (in spanish) (nobody is counting deaths in the same way, and nobody is doing correctly)
4)The situation in Italy
Italy is counting the deaths more or less correctly OUTSIDE LOMBARDY. Lombardy's healthcare system is overwhelmed: people there, in the epicenter of the outbreak, often dies in their homes because the beds in the hospitals are only for the really really severe cases, so many severe but not life-threatening (still) cases are left home, and when their condition worsen, there aren't enough resources to get them to hospital. This is particularly true with older people. Also, people not getting hospitalized in Lombardy are not tested, so those deaths are not counted towards Covid-19 figures.
Link (in italian) (the number of dead people for Covid-19 in Lombardy are not reliable)
Lombardy is the stronghold of the right-wing parties, is the richest region in Italy, it has had a right-wing Governor in the last 20 years and is the most capitalistic one. In Italy, most of the healthcare system is competence of the Regional authorities. Yet, failure after failure after failure, mostly due to the fear of the economic damages, have led the region to shut down late, to count the cases incorrectly, to fall down the mess it is in now. In their favour, we must not forget they were the first ones to face the flying sh*t (unlike other Presidents in the Western World...).
Outside Lombardy, the healthcare system is able to provide treatment, even if only the seriously symptomatic ones are tested and treated. This means, many cases go unreported.
Disregarding the official figures, and given the number of deaths (40% of the total is outside Lombardy, 4000), and using a standard 2% as the death rate where the healthcare system function properly, Italy (except Lombardy) has something like 200.000 cases, half of them between the four regions bordering Lombardy (Emilia Romagna, Piemonte, Veneto, Trentino-Alto Adige).
Lombardy, alone, counted 6.500 deaths, which could indicate anything between 100.000 and 300.000 cases.
This means that Italy has between 300.000 and 600.000 cases.
Link (in italian) (The real number of infected people could be ten times as bigger than what we see - Borrelli is Head of the Protezione Civile, the Authority tasked of coordinating the fight against the virus)
5) Ok, now take the italian data and project them to the specific reality of your own country. Some of them will have data that approaches reality, some clearly won't.
Apart from the known countries who lie and whose figures are very hard to know, how many cases are detected/unreported depend on the testing and counting protocols and capabilities in each country.