I've been making websites for 24 years. Making a website has always been quite hard, especially for a nontechnical user, and there has always been scammers happy to take their money. What's worse is that a lot of the time the scammers believe they're actually selling a good service. There have always been people happy to chuck any old rubbish up on a domain and call it a website, even if it was full of scammy links, stuffed keywords the same color as the background or in tiny text, with JS that overwrote your browser history and blocked the back button, with no context menu, etc etc.
Its annoying, and sad, for those of us who care and consider ourselves professional. But it definitely wasn't any better years ago.
Why is Shopify worth $150 billion? Well, other than the bubble, this effect is why. People can't easily build their own ecommerce sites, can't integrate everything they need to, in a way that doesn't cost them a small fortune.
Wix is a pretty mediocre service, clunky and slow. It's worth $15 billion? How in the world does that happen. Well, building sites is super difficult for most people. The opportunity to make that problem better is, apparently, huge.
Could someone inject links into content in such a way that you cannot find the link in your own source or even your hosting stack?