Intention/use would make sense to matter.
If you bought bitcoin to speculate (and I guess hold it over a year) it would be capital gains.
If you did an online job for bitcoin, I guess you could claim it as income.
What if it was a gift?
I guess if you kept bitcoin and used it to buy something now that the price is higher it would count as bartering if you didn't change it to fiat?

I guess the middle investor is going to be the victim here. Small amounts will be overlooked, millionaires will go to cash havens/change citizenship to avoid taxes and the middle man is going to have to pay up.