To a certain degree I'd say this is apples vs oranges.
Before you shoot me down, let me explain. The reason I say that is because of the core focus of the different platforms.
Signal's priority-one use-case is clearly person-to-person IM and communication. The UI, setup-process and entire architecture is optimized for this one use-case, with all other use-cases being shoehorned in to fit whatever was built for that.
I'd say Matrix (for the moment disregarding a key feature, bridging) has as its primary use-case to be a discord/slack/IRC alternative, to handle "channels", long term group chats and basically persistent online collaboration workspaces.
Sure. Technically speaking, Matrix has a full support for E2E encrypted person-to-person IM and communications (even phone-calls and audio!), and you can use it for that. But this was clearly not the primary use-case Matrix was designed to solve.
Therefore IMO Matrix person-to-person chat has this slightly shoehorned-in feeling, so you may have a somewhat lesser user-experience when using Matrix to do these things than other platforms which had this as their primary goal.
Disclaimer: Happy Matrix-user, running own server, bridging both FB, WhatsApp and Signal into the matrix-verse.