If I look back to ~2017 or so and what I thought could happen with Bitcoin back then, the price is not what most surprised me (in fact, in 2017 we almost saw 20k - not
that far away from the current price).
Instead, it's mainly two things:
First, that its first layer still is the most used. In 2017 I thought on-chain transactions would collapse in 2-3 years and everybody and their grandma would flee either to Layer-2s like Lightning or directly to altcoins. This is of course not necessarily good news: people still hold many coins on exchanges, and retail adoption could be better. Institutional adoption is not something I'm surprised about, it was logical given the popularity Bitcoin had already reached in 2017, but the attention ETFs and similar products, and of course Saylor, are getting in the community, is something I wouldn't have predicted.
Second, that no altcoin came even close to Bitcoin's popularity. In 2017 Ethereum reached half of Bitcoin's market cap in one occasion, and BCH was also close to that mark for a short period. That looks like a very distant past now, with Bitcoin constantly over 50% dominance. And I was among those dumb folks who thought that some altcoins were "better than Bitcoin" back then. How wrong I was
