High tide on soft dry sand is death on any bike regardless of tyre width.
There are many types of "sand" but I find that the most reliable is dry sand up high. It is best to set up the bike, pressures and cockpit to ride dry soft sand and then anything easier is a bonus. To me, death on a bike is a beach that has a pronounced fall to the sea. Riding soft sand with a constant side slope is a sure way to make any man cry real tears.
Riding 90 mile beach for example is dead easy on the dry or wet sand. Venture further north of Cape Conran towards Dock inlet on the other hand and the wet sand is too mushy to ride so you need to ride on the dry. The beach is steep right up to the vegetation line and you need a vastly different bike configuration and riding technique to survive.
As a comparison, 90 mile beach on Bud and Lou tyres - 3psi front 5psi rear and conventional rider weighting front to rear. Dock Inlet, 1psi front, 6-7 psi rear and almost 100% weight bias towards the rear. The front tyre must just skim over the sand and because of the side slope you don't have the luxury of the rear following in the compressed footprint created by the front tyre. Suspension forks in these conditions make the job that much more difficult.
I hate to admit this but I often have a 50mm stem buried away in the back pack to replace the 100mm unit I would normally run for when I encounter prolonged sand riding with a side slope. Makes it easier on the body to maintain an efficient riding position - especially if you're to be in the saddle for hours on end.