Thailand has a history of civil unrest and getting fed up with government leaders. The idea that a country would have 2 coup d'etat's in 20 years and 3 since 1991 is a crazy idea, but that is exactly what has happened in the Kingdom.
This is all pure speculation on my part but I think a lot of this stems from corruption that goes all the way down to the bottom as far as government is concerned and the fact that politicians almost always use their offices for personal gain. Elections are also rife with cheating and vote-buying. That last part is not speculation on my part - several people that I know (Thai people) go to the polls every year and will find out whose representative is paying the most in the parking lot, and then go vote for that person. While this is illegal, it happens every time according to them.
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Every single one of these people are in violation of the state of emergency decree that does not allow for gatherings of more than 5 people after the Royal procession to the Grand Palace was briefly held up due to protesters.
As I stated the other day I think the government was using the motorcade as a reason to implement the restrictions rather than the restrictions actually being justified and they may have actually orchestrated the obstruction on their own.
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This is the first time that these protests have included complaints against the Royal Family as the Royals tend to stay out of governmental affairs in any sort of official capacity but lately, the new King has irritated the population because unlike his father, he is not loved and revered but rather is honored out of fear of police retribution and he has been accused of squandering the countries resources to live a lavish lifestyle despite the fact that he is one of the richest people in the world.
I think it is easy to understand when a massive amount of the country is now unemployed because of Covid restrictions that seeing a billionaire raid the "community chest" in order to travel all over the world with a harem, might irritate a few people out there.
On the 15th the government made gatherings illegal. Unsurprisingly, the number in attendance at the protests immediately grew by thousands. Even after non lethal munitions such as water cannons and tear gas were used, the number of people in attendance grew and grew.
The government has threatened to shut down the internet in the country if things continue which is a bizarre claim but one that could actually work to a certain degree since many people are communicating and coordinating via messenger apps of some sort. Plus social media is as much of an addiction here as it is in other countries. I think it is an idle threat but if it did happen this certainly is not going to make the mob any happier. It could just drive them to violence.
Up to now, Prime Minister Prayuth has defied all demands for negotiations or to resign, which is what the mob has in their "to do" list. However just yesterday he announced that he is "concerned and is willing to have talks."
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Personally I think all of these people should just wait until the next election and vote accordingly. Unless there is widespread voting fraud, you can't just overthrow the government every time your team loses.
From an outsiders perspective this is happening at least in part because the side that lost (and I've forgotten the name of the parties) is what a majority of people in the country's capital or aligned with much like Washington D.C. is 90% Democrat. This is the reason why you see so many anti-Republican stuff happening in D.C. but not in most of the rest of the country.
The same thing is true in Thailand. A great deal of support for the party that is currently in control comes from the North East of the country and 2 of their past Prime Ministers have been removed by similar coups. The only difference here is that the person they are now demanding resign (Prayuth) is the same person that lead the removal of the last government coup.