It is. An 8 bit jpeg has 8.3 stops of dynamic range (the 0.3 comes from some mathematical subtleties) and the last couple stops are hard to see. So, if one's conservative and considers seven stops to be visible for routine viewing of jpeg uploads and adds a couple stops of lifting shadows, then one wants 7 + 2 = 9 stops dynamic range from the original image. That means using less than ISO 800 on a Z7 II or D850 (the two are within 0.05 stop of each other), 500 on a G9, and 400 on the E-M1 III. Comparing ISO 100 on the D850 to ISO 200 on the E-M1 III, as you've done, comfortably exceeds this rule of thumb without the inclusion of noise reduction in post. My G7, with 8.7 stops at ISO 200, is usually fine too.
With a three stop shadow lift this interchangeability is probably starting to break down, since the G9 is at its 10 stop limit and E-M1 III can't quite manage. At five stops a D850/Z7/Z7 II is likely approaching its single frame limits too (Nikon's about half a stop below Canon and Sony at the moment). How much this matters in a practical sense depends on how often one's subjects tend to fall in this range. And, like everything else, it's the folks who frequently encounter limits on shadow lifting who are most likely to talk about it. I would consider
@wyk's post a classic example of this phenomena.
Personally, I rarely lift shadows more than a stop from the G7's base curve. It's common I don't adjust them and I probably lower about as often as lift. So the G7 is nearly always fine to ISO 400 and ISO 800 is normally OK. Its 5.1 stop dynamic range at ISO 3200 is pretty meh after noise reduction in darktable but I've used ISO 3200 for one sequence of images in the five years I've had the G7. Certainly makes it difficult to argue there's much of a practical limitation to the sensor in my use.
Prints have a stop or two less dynamic range than display so they're less demanding in this regard. People are likely to spend more time looking at them, though, and probably have higher viewing expectations than scrolling by an image on a screen. So I agree with
@John King it's more rewarding to really get the tone curve right in a print.
Actually, to me, that much of a lift usually feels kind of fake. You seem happy with it, though, so that's cool.
FWIW, it seems to be around three stops my reaction starts to be more likely "that looks like a shadow lift" rather than "interesting image". Out of curiosity I did a recurve and found I moved the shadows to a four stop lift for this one, which was what I was guessing would be my max lift, and might well take them a third or half a stop lower if working in 16 bit post rather than recurving a jpeg.
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