I have a few thoughts about this:

It probably would be nice to have more programing with English subtitles (and subtitles in other languages) but I’m a bit surprised that such a huge adjustment to daily programing in Japan would be made on behalf of those visiting short-term for the olympics. Of course, it would be open to anyone but the article (and a similar article in Japanese) makes it sound like the olympics and the comments of short-term visitors are primary motivations for the change.
The article says that Japanese content will be “automatically translated by a system to produce the foreign-language subtitles.” Such subtitles might be intelligible for things like a weather forecast, but I can’t imagine them being of much use (except as something to laugh at – because of their poor quality) with variety programs.
Instead of making a major adjustment like this to satisfy the whims of short-term visitors, perhaps the money to make this change could be spent to improve the quality of disaster information and disaster warning systems for people who actually live here.