In this context, dynamic range is really a surrogate for image noise.
Perhaps you usually shoot in 'proper lighting' (by which I think you mean lots of it). I shoot in the light I have, and it's often not very bright, either due to the fast shutter speeds needed for flying birds, or because I need to stop motion at indoor events.
I shoot a lot of birds in flight, and that requires a fast shutter. You mention your preference for the R7 and the 100-500L combo, and for my birding shots with that relatively slow lens, my most commonly used ISOs are at or over 12800.
View attachment 229751
Personally, I would not shoot with an APS-C camera at those high ISOs. YMMV.
The story for me is similar for indoor events – I am usually shooting those with the 24-105/2.8 and 100-300/2.8, and almost all my shots are at ISO 6400 or higher. Here are the ISOs from my 100-300/2.8 shots, for example.
View attachment 229755
If 'proper light' means, for example, in the ISO 100-1600 range, then for me that's a small minority of my images in some use cases.
And once again, the point is not about one sensor size being 'better' than another, but to be aware of the capabilities and limitations so an informed choice can be made based on an individual's needs.