I'd agree with
@SFTPhotography - different sensor sizes/lens systems have optimum sharpness apertures - typically (and there are always exceptions) M43 is around F5.6, APSC around F8, FF around F11 and Medium Format around F16 - all of these roughly equate to F11 on FF - some lenses/systems will be slightly away from these values but its a good guide to get started with.
The issue then with MF (and to some extent FF) is that in the UK you can very easily start to run out of light, so exposures have to be longer to compensate - not a problem with a tripod, but significant winds can then start to have an effect with foliage. Can be solved by bumping the ISO (acccepting the negatives that come with that) to keep shutter speeds up.
Part of the current 'trend' with focus stacking (and this applies to any system) is the 'desire' to have significant foreground interest driven by the fact that many people have UWA lenses and feel the need to use them as wide as possible at lot of the time (and get a super clickbait dramatic shot). This then presents huge depths of field which to get a consistent sharpness on a high MP sensor requires the image to be stacked. If this is your target landscape type shot then you'll need to focus stack whatever camera system you use.
The reality is that many 'landscape' images don't need the use of an UWA lens (I don't own anything that is wider than 24mm on FF equivalent) and Steve's images above were both narrower than that.
I have a GFX50S and have spent a lot of time using it handheld, and I've been impressed with the front to back sharpness even at wider apertures than F16, obviously the higher MP of the 100S may show up a slight lose of sharpness used the same way, but if one was to print the image rather than zoomed in and pixel-peeped I'd be surprised if anyone can tell the difference.