Wheel sets... more spokes or less?

The quality of the build also effects the duability.... so you can have fewer spokes and more durability.
The weight of the rider effects durability.... so you can have two sets of identically specified and built wheels where one wears out or experiences some form of failure due to a heavier rider.

TdF riders pick wheels based on their team's direction. Team sponsorship is important, but the type of challenges expected on the day's stage makes a difference to the choice. No team or sponsor wants to hear about a broken spoke causing a rider to lose out in a stage. However, you will see either wheels or an entire bicycle being swapped out after riders are involved in a crash. More "human" riders don't have the same abilities, sponsors, or other governing factors to allow/make us to choose wheel selections that TdF riders do. A stage with cobble sections is quite different than team or individual time trials.

You might want to look at Uncle Al's rant on wheels at roadbikerider dot com.
Essentially, basic wheels with 32 spokes. Too few spokes leads to too many probs.

The spoke count depends on the rim section. Thin section rims require more spokes to decrease the unsupported section length (span between spokes). But thick section rims were difficult to roll back in the days of the classic wheel so this is where we got 36 spoke rims.

With the advent of better alloys, namely alloys that could be heat treated after rolling, deeper rim sections were possible and with these stiffer rim designs, greater spoke spans are possible.

Regardless of what intuition may appear, wire spoke wheels "stand" on their spokes. Pluck the bottom spoke of anunloaded wheel and then pluck it again after loading. The load is carried by a decrease in tension of the bottom spoke(s) and this is due to the bottom section of the rim assuming a "flatter" bend radius. A stiffer, deeper rim section would deflect less, allowing a greater span.

I've always thought I needed 32 spoke wheels also. But have Velomax Circuits on the new frame, with 22 spokes front/24 rear. At 3000 miles now, they are holding true better than the 32 spoke MA-3 wheels I ran on the old bike.

Had great concern when I ordered them that they wouldn't hold up, just because they had less than 32 spokes. The great performance of these wheels so far has changed my opinion of low-spoke-count wheels.

I have had a set of Rolf Vector Pro's for two years. 14 front/16 rear, about as low as spoke count gets. No broken spokes, and I have yet to have them trued, very solid wheels.