He makes 130k a year before taxes, but has benefits that other normal workers do not. He is making way more than an average middle class citizen in the United States, especially at his age.
The question is do you have a job? 130k a year is more than 90% of combined household incomes in the United States according to the last Census last time I checked. He makes that on an individual basis; yes, he has plenty of expenses, but he also gets plenty of other benefits that other normal workers do not.
Outside the top 100, yes, you're going to be struggling heavily to stay in the ATP. Inside the top 100 though, you should be perfectly fine. Well above middle class. Most middle class citizens are making anywhere from 50k-80k. Around the 90-100k point, you're talking about upper middle class. Past that, you're talking about a very few 10% of the individuals in the United States. Yes, he has alot of expenses, but so do most graduates today coming out of college. The majority of college students that are making big bucks usually hold a graduate degree, so the majority of these people are anywhere from 50k-200k+ in debt (doctors, lawyers, MBAs, etc. etc.), not to mention bills, kids, etc. etc.
130k a year with no debt to begin with (I'm assuming he had some help getting to go pro, so it's very unlikely he has as much debt as your normal college graduate does now adays) is ALOT of money. Even if you account for his expenses, he's still sitting on a huge chunk of cash. That's WAY better than an average middle class citizen, he's upper middle class easily based on his income, and probably has more cash sitting at the end of the day than a vast majority of occupations in the United States (with exception to those in the health field like doctors). His income easily surpasses most white collar jobs starting out, particularly occupations like lawyers or business who usually go out into the workfield with a truckload of debt now adays.