The issue why the province governors are all appointed officials sent by the Ministry of Interior and not elected directly by the citizens of the respective province - like it is the case in Bangkok since 1972 - has come back into discussion as it is one of the campaign topics by the newly founded "Future Forward Party" for the forthcoming long-delayed election, as it is mentioned in this interview with the party founder.
The website isaanrecords has already followed up this interview with two articles on this topic. First, the summary of a talk by Tanet Charoenmuang given in Maha Sarakham in April, describes the history of the local governments in Thailand compared to the centrally controlled administration. Tanet was a strong proposer of elected governors for many years, and I really should get back to read more of his book "Thailand - A late decentralizing country" which contains his old publications on such topics.
In "Core arguments for and against elected governors", an anonymous author again states the administrative history of the provinces vs. the local governments by municipalities. Sadly, there is no comment possible at that posting, so I have to place my nitpicking here. The article states that from 1972 till 1994 there one one municipality in Thailand - which is wrong as there were already 119 municipalities in 1972. However, what is true is that Chiang Mai was the only municipality of "Thesaban Nakhon" level after Thonburi and Phra Nakhon were merged, and until Nakhon Si Thammarat was upgraded to this highest municipal level. The other odd statement in the article is that BMA is responsible for four provinces, but in real it is only responsible for the special administrative area of Bangkok, which is something like a province.
Whereas in Tanets talk the Provincial Administrative Organizations are mentioned, both articles don't mention that these local administrations were changed into fully elected bodies after the 1997 constitution. The the issue of elected vs. appointed province governors was in the political debate in the 1990s, yet the powerful Ministry of Interior at that time was able to block these proposals, and to get the topic from the agenda it gave the electorate these rather powerless local governments in parallel to the centrally controlled province administration.