It will not be only Bangkok having the problem, slowly it will get worse in other provinces as well in Thailand. And recently the government giving incentive for those who buy new car make thing worse, though it has stop now.
Proper, effective Public transport is a key to success . In order to make it happen, the public transportation must be convenient, effective and cheap, so it can discourage people from using cars.
I am proud to say that Singapore act every early to stop traffic congestion. Many Singaporean do complain about incredible car price where you need to bid for a COE (Certificate of Entitlement) before you can own a car, and sometimes price of COE (piece of certificate) can buy you 2 cars in Thailand.
However, I am OK, I did not own a car back in Singapore, but whenever I want to go any where, I can take a bus, by MRT train, or taxi. It is so convenient. I will like to own a car and I think I can afford a car even it is very expensive, but Singapore is such a small country, I am willing to give priority to those who need a car due to nature of job or those that are super rich. I can choose between travel cheap (by bus, MRT) or expensive (taxi) whenever I want.
Staying in Thailand is kind of difficult, you don’t want to own a car because of the traffic, but if you don’t own a car, travelling around can be a pain in the ass. I am staying in Ayutthaya, the traffic is getting heavy day by day, if you get back to your apartment late, you probably don’t find a place to park, even you back early to park, the next day you will find yourself having the push cars around in order for your car to get out. You don’t have a car, there isn’t any Taxi around, just motor cycle transport (dangerous) and it is a one to one service, it actually not very cheap.
So in order for rescuing the traffic, you need to take care of the public transport first.
I actually cannot imagine what will BBK traffic look like in the next 5 to 10 years. And I seriously don’t think Thai government going to do anything about it.