They're wholly made by or outsourced to India (look at the end titles) so the budgets remain relatively low
And they cater mostly to indiefaggots and steamtroons who have been buckbroken by AAA releases and have a grudge against them.
They also tend to make money by being deeply discounted during steam sales and bought by brainrotted morons for 5 bucks to keep in their unplayed collection and forgotten about.