It is not about working on full-time basis as a graphic designer that is the problem but being able to make enough money from working as a full-time graphic designer to be able to take care of your responsibilities that is going to be a problem. Those who are even working normal jobs on full-time basis are finding it very difficult to cope.
This is an eye-opener. I was looking at becoming a full-time graphics designer, but it seems that I won't be able to make the amount of money that would be enough to cover my bills.