Of course blockchain isn't just bitcoin.
But bitcoin is the first currency that uses blockchain technology. That's why there are so many people who swear by it and are willing to put money into it. But that doesn't mean that blockchain technology is only limited to bitcoin, or even transaction making.
Lots of governments are currently launching their own blockchain/cryptocurrency programs, where they aim to have more direct control over the economy and taxation. Blockchain in this instance is applied in a completely different way than bitcoin, since it is centralized.