It sounds like you are worried about a threat model (being identified by your government) that Signal is not designed to, nor attempts to address. There are some workarounds that may satisfy your needs, such as using a different phone number provided by Google Voice or Twilio.[0]

It may not be for you, but Signal does a very good job of solving the problems it does aim to solve for the millions of people who use it.

[0]https://medium.com/@mshelton/using-signal-without-giving-you...

In comparison to what other messaging platforms? What do you mean it requires ID/passport? It uses phone number as a "username", which is why it's easy to use.

Some countries require ID/passport to just get a phone number. This could potentially be sidestepped by getting a Twilio number or Google Voice number, but that causes it to be far from frictionless.

This is like complaining that you need to sign up for the internet using personal info to get onto the net.

Unless if ISP positions itself as rigid security service devoted to provide you security features and some famous people recommend using it in order to transfer sensitive documents.

They do not promise anonymous transfers. They promise encrypted transfers.

Public internet access, both in the form of hotspots and computers, are perfectly usable (if not terribly secure). But you cannot use Signal with a payphone.

Such access is FAR LESS secure for most real humans' threat models.