With Signal you just have to install the App and make an account to start chatting with your friends and family. SimpleX requires me to send a link or QR code to everybody I want to interact with. You will have a hard time convincing anyone to do that. Compare that to the first Twitter exodus, people chose Bluesky over Mastodon because picking a server was ‘difficult’. The average person doesn’t care about technology at all and will always pick the path of least resistance.
It require literally a minute, also creating an account isn’t a thing people like to do.
True which is why WhatsApp, Facebook Messenger and Telegram still reign supreme. Don’t forget that its a minute for each person I want to contact, why bother if I already have the phone number of everybody I know. SimpleX targets a different market than the previously mentioned Messengers, and that’s OK, but it also means its a no-go for anyone outside that market. Signal on the other hand is targeting the same market and thus is a viable alternative and for that reason I could convince my friends and family including my grandmother to use it instead.
Also creating accounts require a minute or more.