Just an update on this - I've also been looking for passenger flights to BKK (again non-tourist - trying to help my sister-in-law rejoin my brother who is resident in BKK).
As
LondonElite says, lots of international flights are shown inbound/outbound to BKK on flightradar24.com. However, when you check the ticketing situation, all flights I can find (checking across August 2020 for various routes - LHR/FRA/AMS/DXB/etc to BKK) are zero'd in all classes.
mg77 - I understand the Thai government is not permitting tickets to be advertised inbound into BKK - only the outbound tickets are generally available. For inbound flights they're essentially either empty or being operated as a charter. The Thai embassy is permitted a certain number of seats per week/month to be sold - the Thai embassy itself (at least in the UK, possibly other locations too) is organising the waiting list (see:
Visa : **Repatriation Flights for non-Thai nationals** - Royal Thai Embassy, London). At the current time, all seats on the UK for August are taken with "update for September 2020 to be posted soon".
If anyone knows of any routes into BKK which are *not* being controlled by the Thai embassies and normal airline booking/capacity is available, please do update the thread.