That's one issue. There's also safety as LSV regulation do not require any crashworthiness tests, so such trucks may be more dangerous to passengers and others (or may not - as there's no mandated bar, we can't really tell how good/bad they are).

I'd think these are not any more unsafe than any other cab-over truck?

We can't tell without comparable tests, which we don't have.

Results from crash testing of the Japanese model aren't great (scored 1 out of 5; higher is better), but since results are only comparable to similar weight vehicles, we can't compare to bigger cab-overs directly, only to passenger Kei cars, where some reach 4 out of 5, with a few scoring the full 5.

The thing is, heavier trucks are exempt from any of it in the US. 2006-2009 Chevrolet W-Series were frontal collision death traps as kei trucks and nobody cared.