... Walker Evans famously shot with a Zeiss Contax (among many other cameras) - which retailed for an inflation-adjusted ~$2,700.
I'm gonna stick with "art is expensive". Yes, good equipment isn't required to make art (a claim I didn't make) - but the reason to have good equipment is because you don't have to fight your tools to get the results you want. Sure, I could fuck around with gels and can lights to get the cool effects I want - but unless I have a stack of ~2.2 million gels, a Westcott RGB point-light is going to be both more capable and critically less time consuming so more of my time is spent doing art than it is futzing around while my model (usually myself) slowly wilts. Similarly, you can produce incredible paintings with a stick and chewed berries - but the time spent going out to pick a bushel of pokeweed, then process that into a usable format, then wait for each stroke to dry, can't be excluded just because it's a more authentic process.
(And don't be an elitist about what constitutes art, either - stock photography is absolutely an art form even if you sneer at it.)