It would be fine if it was a well documented recurring issue that plagued society. As is it, it feels more like a canary in the coal mine, for dirtier times to come.

In practice, most visas are short term, and none of them will allow you to benefit from social aids for very long. At most I imagine you could extend your working visa to 5 years, get sick the first year and be at charge for the remaining 4 years ? There will be ink spent on these cases, but statistically how often does that even happen to need stricter laws ?

The current political climates needs the gov to look "Japan First" and these kind of rule change are very cheap to do, especially as the people directly impacted don't vote nor can complain. It goes well with the very anti-foreigner sentiment, especially as the current wave of tourists is very unpopular despite the money coming in.

The longer view is Japan getting less workers in total, yet more of the worse immigrants as they're calling for people who either don't need Japan (have enough money to go anywhere and don't need to think long term) or are willing to take more risks (high return grifts etc.), in a time where Japanese salaries and productivity are already lower than surrounding countries.

They're basically making a bad situation worse, just for short term political play, giving in on the worse trends.