I sold a domain back in 2011 where the buyer offered to pay via Bitcoin. It was a decent sized transaction. I don't remember the exact exchange rate but it would have likely been upwards of 1,000 BTC.
The answer to that what if is you probably would have sold 80% of them at $30 each, and then most of the rest at $100 each like most people who got them early. Getting back 10x profit is hard to turn up when you have no idea of the future.
At least you sold it. I registered a bunch of great domains when I was a college freshman in 1993. They were free to register, you only had to submit a form via email. I had, amongst others:
grateful.com
eleet.com
cjs.com
snell.com
When Network Solutions won the contract to administer them, they started charging $70/year/domain and I was a poor student and let almost all of them lapse. I lost all of those ones. The only ones I kept were bikeworld.com (registered it for my dad's company) and chrissnell.com. Never made a dime off a domain.
I used to trade domains back when I was in college in 2007 (before the market crashed in 2008). It was still wildly lucrative. You could buy a domain for $10k one day and sell it for $30k two days later.
A lot of people had similar stories: they registered Cars.com or some other major domain back in the 90s, sold it for peanuts, and watched with dismay as it was eventually flipped for 7 figures 10 years later.
I know a guy who, on a whim, registered about 100 double-letter domains (AB.com, AC.com, etc.), then let them expire.
Each of those would be worth a minimum of $250k today
I took cash instead.
I still look back on that and think "what if?"