1. Arguably, the HTTP + HTML web failed. It was designed as a pemissionless hypertext document language, yet more and more of its usage gets rid of every single one of these properties - non-hyperlinkable applications that beg for permission from large monopolies to post something.

2. Success is not the only metric of worth. Nuclear power has "failed" despite being the only reliable solution to meeting the base load of a power grid vs fossil fuels.