MSX1 vs C64

I said depending on situation as in depending on type of music. From what I've heard SID is better at basslines/drums and "synthy" sounds, more suitable for synthpop and upbeat type of music. OPLL works better for more "classical" tunes that require things like strings/trumpets etc. As I said I feel they are all equal because each have their strengths and weaknesses.

And a filter. I don’t think calling the SID an advanced PSG is entirely fair, it’s essentially a subtractive synthesizer (which is the most dominant type of synthesizer nowadays), in a home computer.

But, just like there are people who love classical music and people who love drum ’n bass and glitchhop, there are people who like the FM sound a lot, while others like a more raw (but still complex) sound. Even outside sound chips, some love the Japanese style of compositions, some like the European mod-type tracks more. Some people love arpeggios, some hate ’em. We are all already in a niche anyway, because when I let someone listen to some chiptunes, not many of them appreciate it very much .

So, what I wanted to say with this is, SID is a good sound chip, and whether it is better or worse than low-grade FM like OPLL is entirely subjective. Best you can say is that the OPLL has more channels, which at least is a quantifiable advantage. But the sound generation techniques and capabilities are not directly comparable, the OPLL can not generate the sounds that the SID does, nor vice versa, thus in terms of their timbre they are really complementary. The SCC, too, with its wavetable synthesis. As a musician who wants to expand their soundscape, if you have a subtractive synthesizer, probably you would be looking for an FM or wavetable synthesizer next.

(Although, one could argue with the right tools and moderate CPU support, the SCC can do all three types of synthesis, so it is really superior to all… )

Did you know that PSG can emulate SID as well? Hear this: https://www.youtube.com/watch?v=Zr1r6FSrsz4

Let's indeed not go the 'my chip is better than yours' or some kind of zealous route. Apples & oranges. Some people simply appreciate both their characteristics / strengths and cool tunes that have been created on/for them

I'd like to add the story of Tim Follin here. Arguably one of the most prolific (chip) VGM composers, but, as he seemed to have said at a certain point, didn't really like composing on/for the chips, as he considered them to be mere SFX generators, and not something to compose music on/for. His wish was to work with 'real' instruments (which got fulfilled once Red Book Audio for games became available).

Very ironic thing here, as a lot of his tunes/soundtracks are amongst the most appreciated ones, yet it seems he didn't get much satisfaction out of it himself.

If you don't know the vid yet, or are not familiar with Follin, worthwhile, informative, and fun to watch: Artist Feature #2: Tim Follin (39 min, non-narrated)

There's also the following < 7 min. narrated video: Tim Follin: The Best Game Composer You Never Heard Of

(Btw (for the sake of giving credit where credit is due ;)): his brother Geoff did composing as well, and I believe they did some stuff, soundtracks together (their styles are similar).)

Only if you don't do additional stuff to it and leave everything at default. Indeed, PSG can help, but older MSX games that supported OPLL when it was relatively new tend to use it in a very basic way. It's for instance remarkable that Compile tuned the percussion from the get-go while T&E Soft or even Bit² didn't do anything like that.
I agree that the same is true for Genesis/MD music. There's plenty of examples of Genesis music that is far from cold or emotionless (or "synthetic"/"tinny" as FM sound is sometimes referred to).