Sure. That's why I proposed that an RPG is simulationist if
I'm responding to this one rather than your prior one because its a little more concise and I otherwise will tend to sprawl all over it.
- it intends our real world as a reference, excluding fictions and beliefs,
I don't think it has to entirely do this, if said fictions and beliefs are literally true in the setting. The problem with genre conventions is that the characters are not supposed to acknowledge them, but there's nothing that forbids a simulation acknowledging magic for example, because the characters can be aware of magic.
- it is granular and prescriptive enough on all included real-world phenomena that interest us,
I think that suggests a greater degree of moving target on the word "enough" than is necessary, though. Its obvious that some people's standards are going to be different than others here, but I think you can still say that if a system doesn't make any efforts in regard to a given thing to give you some idea of process, its not simulationist in that particular area. It doesn't require it to be Phoenix Command. It doesn't even require it to be particularly complex (there are some extremely simple incarnations of BRP that basically just have group hit point per body where you hit a serious wound at half; its not a super sophisticated combat model by any means, but it at least tells you that what's happening is, in fact, wounds, and that at a particular point they became serious. Contrast this with D&D hits and notice that for still a relatively simple process the BRP case tells you considerably more).
- the results of the mechanics of that RPG include granular descriptions of what we must imagine in the fiction,
Again, as above, a high level of granularity isn't always necessary, but it the less granular you get the less information you're getting out of it (and of course it may give you actual counterfactuals you have to resolve yourself--D&D's elevating hit point model not only doesn't tell you what's happening, if read literally it tells you things that are ridiculous, so you have to use a lot interpretation to not do so. That's why I claim that its a fundamentally minimalist gamist artifact more than anything else).
- we find ourselves able to suspend disbelief in respect of the results and descriptions of the included phenomena
This is, to be fair, a heavily moving target; its an area where, for example, knowing too much about a subject does you no favors.
- a reasonable player has and needs no alternative to imagining what is described
Uhm. I'd say more that the information is sufficient if they don't feel a need to, but there may still be cases where it can add to the experience. In most combat systems even if it gives the broad strokes more than adequately, there may be some fine details that will be desirable, but that tends to be more in the color and dramatist desire than that to engage with it on a basic level. The big issue is that it tells you at least enough, and doesn't tell you things that you can't make sense of without extending beyond what you've been told.
This puts the burden on the game system to supply descriptions as output along with numbers, but I think we want to go further than that. I think we probably want to say that the descriptions shape future choices and resolutions otherwise they're empty fluff, which we might as well provide ourselves.
Seems fair.