Note that tauri is not bundling entire browser in binary, it's using WebView of operating system instead.
Therefore any comparison should be done on machine that will run your code.
Now here comes one of the disadvantages of Tauri (or its biggest advantage, I guess it depends on you). In your Electron app you write your app backend in JavaScript, because Electron uses the Node.js runtime. Tauri on the other hand is written in Rust. Now if you know Rust you're probably happy, but if you have to learn Rust from scratch (like me) you are going to face some issues.
If you’re building an app that does not require a backend then Tauri very quickly becomes the choice.
I know that some stuff really requires a separate backend (heavy file manipulation etc) but at the same time browsers are progressing a lot and a lot of apps can be created without using a backend, just relaying on the browser engine as is.