Question about bath etiquette

Currently on vacation in Minoh.

Was at a rotenburo when I encountered a Caucasian man with a big towel and his phone. I think he was listening to music on his airpods. I asked if he knew he couldn't bring his phone into the baths but he got quite defensive and after asking if I'm Japanese (I'm not) told me he's been living in Japan 20 years and pays his tax, kind of in an aggro way. So I de-escalated and just went on my way.

What's giving me pause is that an attendant came by after 5 minutes to tell us that the rotenburo was closing and made no mention of the phone. So maybe I was wrong and phones are allowed now?