Depends mostly on where you live but it is not at all impossible. I do discourage everyone however to not solely rely on earnings from Steem as the prices are nowhere near stable and fluctuates too much.
I am from the Philippines where one could buy a simple affordable meal worth only $2-$3 that is enough to feed me, my wife and my child. Assuming the price of Steem is at $1 and I earn at least 5 liquid Steem a day, then food expenses is already covered.
The surprising thing though is that the average salary for common people in the philippines is only around $10-$15 per day. If I earn 20 liquid Steem per day here me and my family can at least live comfortably.
The problem however is the price of Steem in the market. When I first joined here, it was at $8 which now have dropped to $0.9. What's stopping it to go far more below right? And we don't gamble our families future for something not stable.
So yeah going back, it mostly depends where you live at but it is not at all impossible. :)