Advertising platform + Web does not equal "tech company". I've never really been excited about Twitter's tech, since it's mostly just inverted IRC. You "join" people, rather than channels. And channels become hashtags. Then they centralized the entire thing and put a dot-com face on it all. The only way Twitter makes money is by buying out or eliminating competitors, mostly mobile apps. Any high fives for getting crushed by Twitter?

So the tech isn't interesting, nor is the business. The interesting part here is what people are willing to pay for it.