Alot of people sold at around $10K. Probably anywhere from $9000-9900 or so. This is a given. Makes complete sense.
However since the price went up regardless, means there must of been multiple amounts of demand as supply. Hence its extremely bullish.
I am reading many posts on Reddit, or all over this forum people saying "Its a bubble", or "I've sold and will buy back cheaper", etc, etc. I am pretty sure those are the people who sold their entire positions at a profit and are all fiat now.
Its human emotion to talk bad about something that you don't own or want.
I would say that most of the retail market of 2017, they most likely bought it purely out of short term speculation. They bought it at $1000, sold at $2000.
Bought at $2000, sold at $3000. Bought at $3000, sold at $4000. During those huge dips, some people sold at break-even.
The long-term adoptors, the ones who hold Caustatious coins and those who CPU/GPU mined BTC back in the day, they most likely sold very little percentage of their holdings at $10K. I've met many in person and they think $10K is still too cheap.
I really think that most of the coins that were bought and hold this year was by large institutions. They are the ones who kept buying at all time highs because since the beginning of the year their cost basis is still low. But they plan on holding for a long time.