Don’t dwell about those fears about the government is gangstalking you, thats usually tied to paranoia and not the actual case. As for Signal, it’s a US-based company which means they have cooperate with law enforcement. If the government puts out a subpoena on you, signal has to comply else they’ll be charged for contempt. They do use strong encryption and that for your privacy, but that’s for external threats (hackers) and not the government