The reality from those of us actually on the ground working here day in and day out is that the paper's view is designed to sell papers and does not represent the actual situation. I would recommend taking that article with a VERY large grain if salt. Or soy sauce as may be more appropriate. I think tourists will find it tremendously easy to get a cab in Tokyo. That article specifically references Hakone which by anyone's measure is the sticks. Shortages of taxis in out of the way minimal population areas are naturally going to be strained with an influx of tourists. This in no way reflects on the situation in Tokyo however.