Depends on what you are building, but overall I'd say the friction is minimal. For a lot of apps you won't even need to care about Rust whatsoever as you just use a bunch of fairly standard JS/TS api's.

On the Rust side it's also quite nice, easy to make plugins, good api's, all the goodies.

If you do use both the bridge can cause some friction because of serialization. I have personally not had any problems with it. Also good to note that in v2 (is in beta) they are improving this.

Edit: you asked about TS specifically, check out https://github.com/oscartbeaumont/tauri-specta it generates TS types for your Rust tauri commands.