I had the opportunity to witnesses late 90s Roppongi as a very young man.
You could walk into clubs, and many Japanese women would go home or to the hotel with you. They had fun and Roppongi wasn't the place to maintain a fake image. To include some more adventurous women getting down in the bathroom, stairs, building roof tops or area/room just before the roof, parking lots, or parks. It also had a more international vibe than it does today, in terms of the variety of foreigners there.
There also was far less racist Japanese guys trying to block or back talking against foreigners, because they would go to different clubs or didn't care. The mindset was, "Oh, this is a club where Japanese women like foreigners. OK, I'm going to X then." Clubs tended to cater to certain groups. So if you like latino guys you would go to X, White guys than Y, Blacks then Z, and plenty of clubs were mixed rainbow too if you liked all types.
Racism and ultra-nationalism became more prevalent with former Tokyo mayor Shintaro Ishihara coming into office. He ran a political campaign based on racist and xenophobic ideology that TARGETED foreigners for VOTES. The convenient enemy and all of Japan's problems were somehow because of foreigners. Crime, rape, jobs, and even if you were a Japanese guy that couldn't get a date was because of foreigners corrupting the "purity" of Japan. Defending Japan, meant voting for backwards minded xenophobic assholes, who weren't really doing shit for the Japanese voters they duped.
This ultra-nationalist ideology had been there for a while among fringe elements of Japan, but with Tokyo mayor Ishihara it became acceptable nation wide. To understand it's significance from a Western perspective, it's like having a former Neo-Nazi or KKK member winning office, like say White Supremacist David Duke becoming the mayor of New York. Just something almost unbelievable. It's an extremist element gaining acceptability, and with that, their ideology.
This was taught and propagated to younger Japanese, who you have in the clubs now. They are more conservative and sexually backwards than their parents. And by the way, similar ultra-nationalist movements against foreigners and maintaining "pure blood" were happening in Korea too. So this helped feed on each other politically, with new rounds of Japanese, Koreans, Chinese, and Russians going backwards and all hating on each other.
What Roppongi was is gone. The vibe in many clubs is cock-blocking and back talking against foreigners, and chicks in quasi-lesbian groups pretending to each other they are Cinderella and lying like they barely have ever seen a penis in their life. Also because many Japanese guys have heard the clubs are good for pick up, plus with the bias against foreigners, they crowd clubs where foreign men are popular. They will also insult or hate on Japanese women talking to foreign men. At times, local assholes will give Japanese woman that speak English "too well" a very hard time.