[deleted] Signal uses an IP they themselves can't see or access as it is only on RAM and never hits a disk on an encrypted Signal server. If you are using a VPN they use your VPN IP to make connections. This is even better because even if Signal could see your IP (they can't) they just see a VPN IP. If you are using your real IP, they still still can't see or access it as I described.
Signal servers as configured don't log your IP address (just like solid VPNs don't) as I described. It stays on RAM and never hits a server disk and then the IP is deleted. Signal did this with their own open source e2e Signal Protocol - which is the newer encryption they developed to solve the problems with older PGP which leaves a lot of metadata like IP and who you contacted and who contacted you.
By the nature of browser based email, most of the e2e email providers use older PGP encryption. They have not been able to implement the more secure open source Signal Protocol. I'm hoping in the future some e2e email provider can develop a fork of open source Signal Protocol and get rid of the PGP metadata on e2e emails, but for now e2e emails are not high threat model and Signal is. Like I posted, you don't have to share the fact you are using Signal via phone number with contacts if you don't want to and your phone number remains a truncated hash on an encrypted Signal server. For this reason I don't see a big deal with Signal requiring a phone number as they do not have access to it or your contacts (or anything on the app). But hey, if a phone number bothers you, use Session with its small user base. Session works if you have a couple of people who also want to use it with you. If you make your phone number available to contacts on Signal, you can have e2e calls/texts to more people. And, Signal can not see your contacts and they can not see which ones use Signal. All calls/texts are e2e with the key on your phones, so Signal has no access to that. Again, Signal has no access to anything except date app download and date app last used if guv give them a specific phone number via subpoena.