To me, every VST is its own platform. I like the idea of exploring the capabilities of one synth (such as multitimbral synths) - doesn't have to be a silicon chip. KVR's OneSynthChallenge is pretty cool in that regard. Jeroen Tel made a song on FastTracker II using only sine waves. I did something similar only using 3xOsc in FLS (made drums using pitch-sweeped sines). Even the Amiga which some consider 'chip' - each tracker program has its own sound and capabilities.
Of course, this cannot be compared to producing your own .sid, .ay or .vgm that contains the direct chip instructions. And some purists would refuse to capture audio off anything but authentic hardware.
The only issue is that if you use VOPM or FMDrive, you can easily create something that cannot be recreated to play back on hardware. That kind of bothers me, if you market a song as "if the Genesis had 12 FM channels and a reverb unit". You might as well just use modern drum kits and not try to be so close to hardware without being authentic.
But use VOPM + Synth1 with some Linnndrum samples? Without pretending like it could play on a hardware platform? Nothing wrong with that, people will still call it retro or video game music.. make the music you love to make.