More specifically, the internet failed because society decided to dedicate an entire generation of the world’s most brilliant minds to the problem of ad optimization. This directly led to the modern clickbait/ragebait disinformation problem.
If we had just taken those same engineers and said to solve any other problem, it would’ve been done ages ago.
Not DDOS, DOS. You can often crash an unprepared server with one request by telling it to hash more data than it has memory for. See this blog post for a well-known web framework. Let’s say I just sent it a 10GB password, it still has to process that data whether or not the hash eventually shortens to the database field length.