For me it’s the early 2010 internet. Where technological advances made navigating it easy and you could with no effort find several groups chatting about topics you liked. Information was easily available yet it felt extremely personal too.
That was before everything became ultra monolithic and corporate. You’ll be lucky if you find even just one active forum for something you like and more often then not it’s been cannibalised by one of the megacorp pages like YouTube or reddit where interactions are all dull and dead, soulless posting only for menial engagement instead of making friends