There's a difference between document-based web sites like this one and web applications. The potential for web applications has mostly emerged as a side effect of the introduction of JavaScript. Back then, JavaScript was supposed to only add minor enhancements to web sites.
Well... Right here on the the very first website Tim Berners-Lee talks about how to build interactive web applications (here called "gateways"), albeit server-side rather than client-side:
https://info.cern.ch/hypertext/WWW/FAQ/Server.html
There's a difference between document-based web sites like this one and web applications. The potential for web applications has mostly emerged as a side effect of the introduction of JavaScript. Back then, JavaScript was supposed to only add minor enhancements to web sites.
Well... Right here on the the very first website Tim Berners-Lee talks about how to build interactive web applications (here called "gateways"), albeit server-side rather than client-side: https://info.cern.ch/hypertext/WWW/FAQ/Server.html
Money. Ruins everything. And also enables. So it's a win/lose situation.
More than money, it's the curse of going mainstream.