You were right, blockchain analytics was a great startup opportunity and there are already a bunch of companies, like Glassnode, doing blockchain analytics.
You also seem to be missing a lot of interesting stuff happening with cryptos if you think it's exclusively price speculation.
GlassNode's tagline is "Time crypto market tops and bottoms.", I don't doubt that simply analyzing the exchanges is a valid market. But not one that I think is particularly large, particularly not when the exchanges can add their own analytics at any point.
You also seem to be missing a lot of interesting stuff happening with cryptos if you think it's exclusively price speculation.