There are laws in place for service workers related to minimum wage. The employers have to make up the difference if tips don’t meet the rate for hours worked. It seems to me that’s not sufficient for the times.
Hypothetically, if everyone were to stop tipping in the U.S. would things be better or worse for workers? Would employers start paying workers more?
I’m not Japanese but from my time there it seems like no, tips aren’t acceptable unless there’s some explicit mechanic like tip jar or some ritual. I did hear that long term customers tend to bring gifts on special occasions but I think that’s almost never money.