Because grandmas all over the world are getting swindled by scam apps.

Look, I can't locally install a web extension I wrote on an open-source Firefox browser, because security. I have to install a Developer Edition, or get the extension reviewed and signed by Mozilla, for the very same reasons of thwarting scammers. Is this stifling, or is it making my browser not mine? Is anybody making a big deal out of that?

The world we inhabit is not always friendly. It has a ton of determined and sophisticated bad actors, and a lot of people with less technical savvy than you and me. We have to deal with that, instead of being cantankerous.