This is a difficult discussion to have with only imperfect data available.
But I'll take your reddit poll at face value. I agree with Papa Sweet, the market will skew these numbers widely. I can't imagine finding an SB who looks decently hot in Los Angeles for $200 ppm. I do find an adequate number in the $300-$400 range, but I also regularly get asks for $500+, maybe 65% of the time.
I have also had a mix of SB's who (I believe) stay with me alone for 1-3 years (4.5 was the longest) and others who have a pretty full dance card. I don't ask, and I don't tell (them). For those SB's who take sugaring as their primary source of income, a $50-$70k annual take is not unreasonable. But again, most of the SB's I get to the BCD stage do this for supplemental cash; some for unpaid needs like bills, some for wants and desires like clothes and designer crap.
To be sure, there are SD's who can easily afford to drop $300k a year on sugar pussy. I've known a few along the way. One of the 1st I met was my role model back in the late 2000's for how to live this life. He was a very successful lawyer (corp. litigation) and my best guess is he was spending $350k a year on sugar, so his total annual pay must have been north of $1-2 million (he had a wife and 2 teenage kids). But when he had to go on travel for a meeting or a court trial, he would pick out his favorite stripper from an upscale club in LA (4Play for those who know...) and take her with him for a 2-4 day trip. He'd get fresh sugar after his meetings, and she would get cash and a new pair of Jimmy Chu's (or maybe 3 pairs).
When I really got a good look at what he was doing I knew: I wanted that!!
So the numbers from reddit are at least plausible. And I expect that those SB's pulling in north of $100k a year are in the top 1-3% of all SB's.
Life is good
The Cat