It's a RAM issue not a disk space issue. Binaries get loaded into memory.
Also if you haven't heard, disk space is no longer as cheap, and RAM is becoming astoundingly expensive.
I'm pretty sure Tauri uses almost as much RAM, you just don't see it because it gets assigned to some kind of system process associated with the webview. Most of the RAM used by a browser is per-tab.
My Native macos app was using well over 1gb the other day, while my electron notes app was 1/5 of it. Theres an electron tax for sure but people are wildy mixing up application architecture issues and bugs with the framework tax.