People have been selling photo to painting schemes for decades. There's a mini-industry where you send in a photo and get back a paint by number kit. That predates computers. Etsy has a whole category for photo to painting shops.
There's a reason we have the expression "starving artist." Most people don't really want to pay for art.
If this is a means to monetize their skill so they can survive, it's understandable they would jump on it.
I'm a writer. Similar problem. I earn money working for a service where I get paid relatively little to write the kinds of website content that gets decried on HN as having ruined the internet. HN members expect high quality content on the front page on a regular basis and also uses ad blockers, posts ways to get around pay walls, etc.
Some of my original content occasionally hits the front page of HN. In January, I had a piece get 60k page views and 300+ comments. It didn't make me one thing dime. It took me about two weeks to write it.
I haven't done a follow up piece on the parenting site in question. Instead, I'm writing more stuff for pay that HN members decry as ruining the internet.
The world gets what it is willing to pay for. And then it says ugly things about people taking the money, like artists should prefer starvation to doing this thing we will pay them for when the reality is most of them can't find another way to pay their bills.