The SoundFont format was developed by E-mu Systems and Creative Labs as a way to store wavetable synthesis data. Despite the rise of massive, multi-gigabyte VST instruments, SoundFonts remain popular for three reasons:
Most old SoundFonts are tiny (often under 50MB), making them instant to load. old+soundfonts+work
You might find files ending in .sf3 (compressed) or .sfz (text-based). Most modern players handle .sf2 and .sfz, but .sf3 is primarily used by MuseScore. The SoundFont format was developed by E-mu Systems
The "General MIDI" sound of the 90s is a specific aesthetic currently trending in lo-fi and synthwave. multi-gigabyte VST instruments