The last time I went to Golden Gai was May, 2022. And I've also been to other bars in Tokyo and Yokohama, usually about once a month or two, often to "live houses" where bands would play.
Among the big differences in the past years is that a lot of bars now keep their doors and/or windows open for air at all times, and this includes winter. Same thing for local trains and buses.
Also, restaurants tend to take orders only up to around 8:30pm. So, for example, if you go see one of those three-hour movies in Hibiya in the evening, there would hardly be any place to have beer before the movie, and when the movie is over the beer places would be closed. But you do have the option to enjoy non-alcohol drinks and meals earlier in the evening. Some bars would close a bit later, but no later than 10pm. By the way, movie theaters still do late shows.
When drinking and dining, people pretty much chat with their masks kept off. So, among the unwritten rules in tiny bars like those in Golden Gai is that you leave when it starts getting crowded, so that others could drink safely.
A lot of drinking/dining places have big plastic shields standing between customers. But if you're with close friends or family, you can ask to have them removed and they'd quickly take it away for you.
Whether or not people shout while drinking pretty much depends on the bar rather than the person or district. TV tells me that some bartenders are against masks, but I've never actually met one.
I don't do karaoke, but the last time I attended a party, it so happened that a karaoke place was the only place available for our after-after party without reservation.
But in my opinion, heading home by 10pm is healthy. You can still have a lot of fun at dusk.
Golden Gai has a Facebook account. Feel free to update yourself through their photos.
https://www.facebook.com/goldengai/