the two main ways (in my opinion) that foreigners are here are those on retirement visas, which require you to be 50 years and older and now those on DTV, which are remote workers, etc. you then have the teachers.
I believe so. My understanding is that all non Thais (unless you have a specific visa that says you don’t have to) are required to report every 90days. Not sure why people are so concerned though. First time in person, future times online
The Ministry of Foreign Affairs has been very clear on this. You can’t convert visa to DTV and you can’t apply while in Thailand. If your friend did so, it was against the rules
technically it is not allowed. That being said, some people have cheated the system into thinking they are outside of Thailand and have been successful.