I tend to agree Warin, a lack of bridges over water crossings close to trailheads do act as a pretty decent regulator of not only walker numbers but dare I say experience levels. Few would argue that if you're not prepared to get wet feet (and legs, waist and everything else) then you probably shouldn't be out in SW Tas.
That said there's probably a safety argument for bridges 'deep' in certain walks to lessen walkers getting stranded and potentially needing rescue. Again though, experienced walkers know it's a potential risk and plan their trips accordingly to allow for unexpected layovers to wait for levels to fall.
Mind you, Pass Creek would be a reasonable candidate for a bridge. Unlike Seven Mile and Strike Creeks which are broad, shallow and easy enough to ford unless it's pumping, Pass Creek is narrow, tight and would become dangerously un-ford-able within a day of decent rain. I suspect as far as PWS is concerned though it mainly comes down to the cost of building (and engineering) such a thing and being realistic as to how long the thing lasts before it either gets burned in a bushfire or washed away in a flood... every creek crossing we came across had one or more snapped roped lines from (I presume) massive winter flooding. The sizeable collected mass of timber bridging Junction Creek I saw 18 months ago has been quite reduced after two winters.
Coming across Big Bird One was a surprise. I only wish they made its webcam public for viewing. Then we could have seen the trip probably wasn't going to be worth it before walking 30km+ in!

We made the summit of The (Namaste) Needles but only just, I don't think any of us have turned around from a summit so quickly. Not very nice conditions at all - honestly a bit silly to have been up there. Very much a relief to get back down off the ridgeline and into the valley.
Of course the weather for (part of) the walk out was quite lovely... :-/ #novemberweather