What is the possible punishment for violating the law on the storage of user data in their country of residence?

Question

Law in IT

Precondition

I am developing a social network, in which I still have to store personal data about users. In the question, I consider the Russian Federation and refer to the Federal Law on the storage and processing of personal data in the Russian Federation .... I am not a citizen of the Russian Federation, and my rented servers are not located on its territory, although not a small part of the target audience is from the Russian Federation.

Questions you are interested in

1. Is this law mandatory? I mean, is it possible that there are some nuances in it that allow you to store personal data not only on the territory of the Russian Federation?
   
2. What is the punishment for violating it? As I understand it, the maximum punishment is the blocking of the service on the territory of the Russian Federation?
   
3. The concept of "Personal data" is very vague, even in their comment they describe it like this:
   
   

   “Personal data is any information relating directly or indirectly to an identified or identifiable natural person”
   

   
   Is there some more definite and not so abstract interpretation of “personal data”, perhaps some ready-made examples of how this law works?
   
4. What other countries oblige to store personal information about their users on the territory of their country? Still, perhaps some countries in Europe that have not ratified the CE Convention on the Processing of Personal Data of 1981? If so, which ones?
   

Remarque

It is also worth clarifying that this issue interests me exclusively from the legal, and not technical, side. Storing data about users locally, in their localstorage, hashing before sending, and other methods I find unsafe.

I received the main information on the issue from this article on Habré, so I apologize in advance if this information is outdated.