Most sites are built on lots of unaudited untested (by them) third party code sever side. Adding some client side isn't great, but also isn't a fundamental change to the dynamic.
(I used to make web server software)
(I used to make web server software)
If I was the mean person at IBM that buys startups and makes them "right", it's a lot more work to fix terrible added to terrible than plain terrible. And my last startup got bought by IBM, so I've experienced that pain personally.