FWIW, I use the same light meter for my meterless 35mm cameras as for 4x5 large format. Any concerns about "total light" and light gathering ability of available lenses are baseless unless one is doing astrophotography.
That aside, there is the matter of DOF being more precious with the larger format such that f/5.6 is a fast lens on 4x5 and even that may be hard to manage without using the camera's movements. Medium format is not a whole lot better. Consider the traditional Pentax lineup of lenses for 645 and 6x7; yes, f/2.8 is the norm for a "fast" lens of moderate focal length and it is not a matter of physical size.
Faster apertures are unusable. It might be noted that ISO 400 films are very popular for natural light photography with larger format due to the freedom to use shorter exposure times and the happy coincidence that the larger format "eats" grain due to less magnification being needed for enlargements.
I noted the use of camera movements. They exist, at least partially, to allow for adjustment of the focus plane to help compensate for low DOF. The article mentions bellows extension. Yes, that reduces effective lens speed, but the case is overstated for all but tight head shots and table-top work. The rule of thumb is no compensation at less than 50% extension (~1/2 stop, 1:2 "macro") from infinity.
Now, in regards to medium format...Have we ever read about the so-called "medium format look"? Generally that means some form of splendid subject-to-background isolation. Surprise! That look comes at a price in terms of shutter speed and ISO, though it is not as steep as with large format. Examples with EXIF from the medium format area of this site as well as a survey on Flickr might provide a reasonable sampling of where the limits are. I can provide a few examples from 6x7 negatives. Sorry, if I took notes regarding aperture, I could not find them...
Chamonix 045N-2 (view camera), 6x7, 150mm, unknown aperture, hand-held meter with no bellows compensation or movements used, Ektar 100. Chamonix 045N-2 (view camera), 6x7, 150mm, unknown aperture, hand-held meter with no bellows compensation, significant use of swing and tilt to adjust focus plane, Ektar 100.
It is unlikely that this shot could have been made without use of camera movements.
Chamonix 045N-2 (view camera), 6x7, 150mm, unknown aperture, hand-held meter with no bellows compensation or movements used, Acros 100. Chamonix 045N-2 (view camera), Token 4x5" for comparison, 150mm, unknown aperture, hand-held meter with no bellows compensation, swing and tilt used to adjust focus plane, Arista.EDU Ultra 100.
Yes, movements were required for this shot. IIRC, I was using f/22 or thereabouts. Note that the trees in the background are OOF.
Chamonix 045N-2 (view camera), Another token 4x5" for comparison, 90mm, unknown aperture, hand-held meter with no bellows compensation, swing and tilt used to adjust focus plane, Arista.EDU Ultra 100.
Yes, even with a wide angle, DOF is an issue at moderate distances (the near foreground was about 4' distant). I was able to use a longer exposure here (~2s) and due to dim light, I was probably no wider than f/22, but still had to use both swings and tilts (front and back) to provide adequate near-far focus.
Steve