BTCUSD is not the only pair, there are hundreds of coins.
But if we focus on that pair how can anybody say it is not profitable?
Buying JAN 17 for $1000 selling JAN 2020 for $10,000
Buying JAN 18 - no propfit/loss
Buing JAN 19 for $3000 selling JAN 2020 for $10,000
Not talking about buying JAN 17 for 1000 selling DEC 17 for 20,000
The only mmnt it was not worth it is DEC17/JAN18 for that 20,000
But these are just 2 months all other months it should be worth it.