Makes sense actually, I didn't stop to think about what my required Thai covid insurance actually covers until I read this article. Health insurance only normally pays for medically required treatment, if you are asymptomatic there is nothing to treat medically. I can see an insurer saying we are not going to pay for 10 days at a hospital when there is nothing the hospital is going to do medically. Just because the Thai government requires quarantine at an authorized facility at cost does not make it a medically accepted procedure to treat covid.
When I applied for my Thai Pass it just said I need Covid 19 coverage of minimum USD50,000, I don't believe anywhere did it say the insurer had to pay for mandatory 10 day hospital stay based solely on positive test. That's something I think the Thai government needs to require in their next update to entry requirements.
Like if you get in a car accident your insurer will pay to fix the damage, but if you get into a near miss they aren't going to pay for a tow to the repair shop and pay for an inspection and 10 days storage fee when there was no contact or damage.
Although, for the ones refusing to go to the hospital or Hospitel they should have read the fine print of their policy, but then again who does until its needed?