Actually I have to go out of my way to run Zoom in the browser instead of using the installer. I have to use Chrome instead of Firefox, download but not install the app and wait for the "or run in browser" link to appear after that.
I really don't like macOS installers anyways and passionately hate them as "installing" and App on macOS should be nothing more than moving the .app from a zip or disk image into your /Applications folder. I just don't trust them in not placing additional crap like auto updaters or kext's when I don't need them.