Thank you - I understand it now 🙏
I guess "uncles" are common problem sources everywhere
全裸中年男性 (naked middle-aged men) is a one of meme in Japan. Most of they are fictitious, but occasionally they are real.
Because middle-aged men cause so many problems in Japan, " naked-" is added critically or self-deprecatingly to characterize them when referring to such middle-aged men.
https://dic.nicovideo.jp/a/%E5%85%A8%E8%A3%B8%E4%B8%AD%E5%B9%B4%E7%94%B7%E6%80%A7
https://dic.pixiv.net/a/%E5%85%A8%E8%A3%B8%E4%B8%AD%E5%B9%B4%E7%94%B7%E6%80%A7
Discussion
So sad to think that I'm getting closer to being an "uncle" every year😇