It’s not that confusing. To a user it could be the same as an app, just one you can be prompted to “install” instantly without a download and without wasting space on your device.

If Apple weren’t incentivized to block PWA use, they’d allow them to be “installed” with the same type of little top banner that prompts you to get/open an App Store app. Instead they relegate it to some obscure buried option inside the Safari Share menu.