Whatever its legacy is today, the lo-fi movement from the mid-1980s to the 1990s allowed more musicians to get their ideas out there. Without having to shell out extra money or go through some sort of gatekeeper, many recorded their albums through very inexpensive tape recorders or boomboxes - the term "lo-fi" being coined in reference to subsequent quality of sound, which was lower than that of the industry standard at the time.
Lo-fi served as a means of tearing musical boundaries down, to allow for complete accessibility. It showed that sound quality should not matter to a musician if they can write interesting music.
Many of the most well-known albums associated with lo-fi have a deliberately ruined aesthetic, as artists merged pop sensibilities with off-putting experiments in noise. Lo-fi showed that albums could be colorful murals of genre, rather than having to submit to a standard form, as a movement it was a great equalizer. It allowed anyone and everyone to record their music and get it out to an audience, and it shined a spotlight on artists that may have never received attention from the major music markets otherwise.
More important than any of that though, it produced some brilliant and original albums...