I always figured telegram got the screws turned on them all the time because their lack of E2E encryption meant it was viable to demand they proactively police the platform in the first place. Maybe Signal would just be outright blocked in these locales if it was anywhere near as popular, though.

They generally don't have to proactively police it, but they have to answer court orders in every country that has courts, or they'll be in trouble in that country. And countries are free to cooperate with each other to enforce these.

Pavel Durov was arrested when he traveled to France because Telegram was noncompliant with French court orders. You can ignore them in Russia... you can't ignore them in France. And you can ignore Russian court orders in France but not in Russia. And the Russian or Indian court is free to ask the Montenegrin government to suspend your domain name and the Montenegrin government is free to agree or disagree.

Signal is already well known to governments. In fact a few years ago there was a report in the UK media about how some governments used signal instead of official channels like email and did so because of Signals disappearing messages feature (ie making those MPs less accountable).

in fact, telegram does support e2e encryption ("secret chats")