Honestly they should post this somewhere more conspicuous than a hotel in northern Japan if they want humanity to get the message, maybe at the Shibuya scramble or Times Square.

For early beginners, I've heard good things about Nihongo con Teppei and Japanese with Noriko.

For N3-ish to early N2 level, あかね的日本語教室 has a lot of quite short episodes that are easy listening and that review any potentially new vocab at the end.

For N2 and up, I'd recommend listening to regular podcasts in your area of interest, or selecting audiobooks from Audible then giving a first pass listen through to get the general gist, then re-listen but look up any words you don't know and ideally add them to a review list somewhere, then give a third pass through by which time you probably won't need to look much up. Repeat until you feel like you understood 100% or get sick of the episode/book. If you're into computer science, I've found ゆるコンピュータ科学ラジオ easy-ish to follow. For general science topics, though leaning a bit towards biochemistry, biology, and chemistry, I've found サイエントーク relatively easy to follow and a good source of new vocab.

In terms of audiobooks, I can recommend the first audiobook I listened to, which was 神の子どもたちはみな踊る by Haruki Murakami. The stories are all relatively short and written in simple language.