Yes, that's a problem with MIDI 1.0. There are a few ways to work around it. Some synths support custom tuning tables, and there's even a MIDI spec for custom

Yes, that's a problem with MIDI 1.0. There are a few ways to work around it. Some synths support custom tuning tables, and there's even a MIDI spec for custom tuning tables called MTS that hardly anyone actually implements as far as I know. One way that works for multitimbral synth (which a lot of 90's romplers are) is to only play one note at a time on each channel, and use multiple channels for polyphony. This allows you to individually control the pitch of every note. The one-note-per-channel trick works okay, but it's kind of awkward. If you want to use all 16 channels, it means setting every channel to the exact same patch, which is tedious. Also, you have to know what the pitch bend range of the synth is if you want to bend by the exact right amount. So, eventually MPE was adopted as an official MIDI standard to provide an easier, more user-friendly and standardized way to do one-note-per-channel MIDI. MIDI 2.0 has added per-note pitch bend. For anyone making microtonal instruments right now, though, I'd say MPE is probably the best/easiest option.