The new 45 Baht fee

According to the agreement between the Expressway Authority of Thailand and its current licensee, all Bangkokian will have to pay an additional of 5 Baht per each entry to the system.
The new incremental will sum up a total of 45 Baht (1.5US$) per entry for a 4-wheel vehicle.

During the past decades, the entry fee to the Bangkok expressway system has been dramatically increased.

From a 10 Baht fee at the introductory stage (1983 to1992) to 15 Baht in 1993.
Next, it was risen up again and again to 30 Baht, then to 40 Baht respectively.

I know that the additional costs have been utilising for a better and greater services and safety; the newly asphalt road for a smoother run.

But...how come the traffic is still as bad as before??