> And lots of those companies went bust, quite a few spectacularly so.

pets.com "selling dogfood on the internet" is the major example of the web boom then bust. (1)

But today, I can get dog food, cat food, other pet supplies with my weekly "online order" grocery delivery. Or I can get them from the big river megaretailer. I have a weekly delivery of coffee beans from a niche online supplier, and it usually comes with flyers for products like a beer or wine subscription or artisanal high-meat cat or dog foods.

So the idea of "selling dogfood on the internet" is now pervasive not extinct, the inflated expectation that went bust was that this niche was a billion-dollar idea and not a commodity where brand, efficiencies of scale and execution matter more.

1) https://en.wikipedia.org/wiki/Pets.com#History