When you use the word 'logically' you raise the stakes somewhat. Ever heard of the fallay of the illicit negative? It means that your reasoning is based on false premises. So, let's look at what you wrote from that perspective.
When discussing "Crop" cameras compared to "FF", we always view it from an exclusive, "What crop cameras lack, compared to FF" POV.
Who is 'we'. Do 'we' really 'always do this? Not that I'm aware/
But I think when we view it from a "What FF lacks compared to crop cameras, it becomes less clear. And the issue is rarely viewed from that perspective.
Full disclosure, I am a satisfied Olympus m43s user, and I believe that the m43s, and Fuji communities (including the manufacturers) have done a terrible job in trying to steer the narrative in their favor. I'm going to use what I know best, which is the Olympus m43s system as an example, but from everything I've read, much of this applies to Fuji cameras as well as the seemingly abandoned crop cameras of Canon and Nikon as well (at least theoretically, we can't account for Canikon's marketing decisions).
M43s offers a significant Depth of Focus advantage over FF, allowing more forgiveness of sloppy focus techniques. Useful in birding, news, and other action photography. When I need a shallow DOF, there are workarounds, not only including larger, heavier, faster, lenses, but longer lenses, and software solutions. In the meantime, though VERY small and very good lenses, both kit and pro level, and some in between, are available for the times when DOF is not an issue.
This premise is false. mFT does not have a depth of field advantage. In fact it's at a disadvantage, because whilst FF can achieve as deep a DOF as mFT, up until diffraction blurring is a significant issue, FF can offer shallower DOF, so it allows a wider range of DOF effects. That's to its advantage. Your statement relies itself on two false premises. One is that deep DOF is somehow 'better' than shallow DOF, and second, that an FF camera cannot be stopped down.
The truth is, IBIS is MUCH easier to implement with a smaller sensor. I've read that the Olympus 5 axis IBIS has gotten to the point where the next step in IBIS is to account for the rotation of the earth. I don't think that advantage is going away. And in my opinion, THAT also mitigates at least some of the advantages of a larger sensor.
This premise is false. IBIS
may be
a bit easier, but it's not enormously significant.
Noise, and dynamic range is quite good on my E-M5 III (and my E-M10 II, FTM). I concede FFs extreme low light capability, but up to about ISO 6400 it simply is not an issue, particularly when viewed through the perspective of a wildlife and action photographer.
It's simply not an issue
for you. It certainly is for some other people. We have seen some very well known people on the mFT forum make the transition to FF and who now claim the get noticeable image quality improvements at low ISOs.
The truth is, I will stack my m43s photos against any other brand of camera (FF, & smaller) out there in normal viewing situations. But I will have the advantage of size, weight, cost, and reduced camera movement 95% of the time.
That might be true, but what you are willing to do really doesn't add much to your argument. You might be willing to do some very silly things indeed, we just don't know.
Context is everything, Crop camera users (esp non m43s users) can you think of other things FF lacks compared to your system of choice? I'm genuinely NOT interested starting a flame war, though I concede it is possible if people think with their backsides and not their brains.
I have two systems of choice. One is mFT, the other is FF. I think they are different horses for different course. I wouldn't argue that either is in any absolute sense 'better' than the other.
But I'd like to see the reasons you continue to use your crop system cameras.
I can't see where the 'logically' bit came in.
