Personally I’d go with Independence Day if I had to pick a movie that felt the most 90s.
Definitely The Mummy starring Brenden Fraiser and Rachel Weisz
Home Alone. It’s a movie that really couldn’t take place today due to cell phones and the Internet making easier to communicate with someone if the landlines are down. Also, the family wouldn’t have been able to get through the airport like they did back then thanks to 9/11.
Clerks
Clerks is a lot closer to real people’s experience of the '90s, as opposed to quintessential '90s fictions, like Pulp Fiction or Hackers.
Yall probably forgot about Hackers because it’s a documentary but it’s pretty 90s
the fashion, music and hyperbolic/complete misunderstood depiction of cyber security cements Hackers as the quintessential 90s movie