It's end to end encrypted
open source and it's a non profit
Idk what better app there is for privacy
there's multiple FOSS E2EE messaging apps out there, theres many not flaws but things that other apps do much better which is why I think signal isn't the best
1.KYC needed for an account, now its common sense you shouldn't use your main phone to make a signal account, but some retards prolly used their main phone to make an account, I don't even need to explain why that's bad opsec
2.Its not decentralized, theres other E2EE Open source messengers that are decentralized so how can u claim signal is the best messenger
3.Signal has user ids
If you want as much privacy as possible you don't want any identifiable info
4.Better alternatives
SimpleX: No user ids, can route through Tor, E2EE, Open source, Decentralized
Session: Uses Tor by default, E2EE, Open source
Onionshare: send files, chat over tor anonymously
Signal is good for a convenient privacy messenger but not the best by any means