This is not what it says on the web in general and antivirus companies, avast, Kaspersky ... In steve108's link, microsoft also says that the pin code can be as complex as a password with special characters, uppercase, lowercase and numbers, so pin code only with numbers is not sufficient.
According to the article with windows hello it seems that the pin code with only numbers and short is sufficient but I believe that you need a computer with tpm and activate it to have an asymmetric key (or pair of keys). I used windows hello with the fingerprint without enabling tpm...