You're right: it's surprising that winning a 6 day second division race isn't worth more than that.
By the way, eighteen (?) World Tour teams times a max roster of about thirty riders is 540 riders, not 1200. Has the maximum roster size changed?
With a start list quality ranking of 3 this is way way below a second division race. I doubt it fits anywhere, other that an amateur race.
As I indicated, 19 WT plus 25 PT (ie 1st & 2nd Div) is approx. 1200. These are the guys generally accepted to be the professional road peloton.
I doubt there are any pros in the Thai race, which is why PCS has asked the UCI why they have allowed this to happen.
Even the compacted season and riders having to prioritise in bigger races they still have full fields of pros.
As an aside rosters increased to max 32 for 2021