Tor has decentralized nodes, signal is a single central server with no verification of what’s running on it ( that also uses phone numbers, which are tied to you identity, as its primary identifier). Also as a US company it’d be illegal for them to disclose if their server has been compromised.
The Tor project is also funded by the us government, that doesn’t make it less secure.
With open source software you don’t need to trust that nothing shady is going on in its source code.
Tor has decentralized nodes, signal is a single central server with no verification of what’s running on it ( that also uses phone numbers, which are tied to you identity, as its primary identifier). Also as a US company it’d be illegal for them to disclose if their server has been compromised.