He has missed the real issue by miles. People never visited Thailand for better trains. They visited because it was exotic and different and not over run by hordes destroying the environment.
They accepted less than optimal infrastructure because it was cheap, cheerful and friendly.
Now it's expensive, not cheerful and not friendly.
I loved Thailand when I first arrived, and made it my go to place for decades. I wouldn't be interested now.
If they want to make it popular again they could start by 90 day visa exempt stays renewable by a border crossing indefinitely, like it was for NZ decades ago.