Essentially if you want a further explanation of how "moe" as a concept came to exist, a proto-moe culture already existed in the 1980s with the bishoujo and lolicon communities, which were primarily manga and anime based and regulations were far less strict in the 1980s. A combination of the economic bubble collapsing and Japanese conservatives regulating shit around 1990 in response to two high-profile cases of otaku raping and murdering children, caused a dramatic shift in anime for a years where it doubled down on focusing mainly on appealing to children rather than young adults, and bishoujo/loli manga was harder to come by in the mainstream, along with the perfect storm of PC games becoming popular, drove a lot of otaku to PC games. VNs, dating sims and gal games became the new frontier akin to the boom in ecchi OVAs in the 80s and it was in this VN/dating sim/gal game scene where moe became more defined and refined as a concept over and over again.

A combination of Evangelion causing TV stations to back down on over-regulation, and the popularity of moege saw an explosion of "moe" influencing mainstream anime and manga in the mid-late 90s and even moe-focused anime being made in the late 90s and throughout the 2000s.

The early-mid 90s was sort of a "lost decade" in otaku culture and the moe that popped up in the late 90s onwards was kind of an explosion of an underground subculture and idea that grew on early messageboards and video games/visual novels.