It wouldn't at the least surprise if it is true. Most of the time I spend in Japan I have similar tales of general weirdness that could only happen in Japan.
Example, I popped on a Facebook page dedicated to Tama-chan, the Station Master cat for an article I was writing for the Washington Post, odd news column. I got in a side conversation with another used for a couple of weeks. All I knew about her was she was from the UK, loved cats, and hoped to someday see Tama-chan. At that time, I had plans on going back to Japan for work anytime in the foreseeable future.
Time went on, and I totally forgot about the FB page as, well there was no more conversation to be held. Didn't even know the woman's name. A year later, I ended up in Osaka for business, and while there, a friend of mine called me and invited me to her farm about an hour from where Tama-chan lived in a city outside of Wakayama.
After visiting my friend's family farm, I hopped a train for Kishi to see the Stationmaster Cat. At that time the station was torn down for renovation and the caretakers for the cat stated the cat was in their private home and to come back a few hours later. So, as a train buff, I hopped a local train and randomly got off up the line to take pictures. Hopped back on the Strawberry Densha, which was totally empty, except for two gaijin at the front of the train.
This in its own was really odd, seeing two foreigners on a remote railway line a hundred miles from Osaka, in the middle of the Wakayama countryside. So, they spotted the only other white guy to been seen in days and started chatting. They were heading to Kishi to see Tama-chan. Turns out they were from the UK.
Long story short, the husband went on to say his wife drags him all over the planet to see famous cats. Ends up the woman who was on this train, was the very same woman I had talked too over a year prior on the FB page.
Most every experience I have ever had in Japan has fallen along those lines; something that I can not say about any other country I have had to travel to.
So, going back to the original quote, I can completely and totally see, the tale of Densha Otoko being spot on real.