I find it amazing to have this type of discussion after decades of skiing on sintered ski bases, but even to this date there are debates on the effect that waxing has on ski performance and how it all works.
As a skiing and ski racing aficionado, you must have an opinion on this, so let's have a closer look at the issue. The reason we're even contemplating looking at it is because there is one "study" claiming that waxing does not make the skis faster.
We wax the skis for a number of reasons. The first, in my mind is consistency of glide: if you don't wax, the ski will behave differently over different snow, given the grind type you have on your base.
A secondary reason we wax is so that the skis are faster in some types of snow.
A third reason is to protect the bases - this comes last, because the reason we want to protect the bases from degradation due to the abrasive snow is one of the above: maintain a consistent glide and be fast.
Remember that we ski on edge, either carving or not, so the wax will wear off faster right next to the edges.
The basic issue is whether waxing with the appropriate wax is faster than not waxing and, interestingly enough, this fact is agreed upon by everyone, even by the guy that made the study of "waxing is BS", which I won't link to.
The study says that in dirty snow, the waxed skis become slower after a while, after somewhere between 200m to 3.8km. That's longer than an alpine ski race so the point of "is waxing faster" is moot for racing.
It is true on the other hand that waxing with the wrong wax, can make a ski slower than not waxing it at all. See below.
We mentioned that, sometimes, waxing with the wrong wax can make a ski slower than not waxing it at all.
That is especially true in two conditions:
In the first condition, apparently no wax is better, although high-fluorinated wax is normally repelling dirt as well. So, it has to be very, very dirty, a condition apparently encountered at a Nordic World Championship race in Thunder Bay, Canada in 1995. I have seen quite a few mentions of this specific race, so it is very unlikely these conditions are common.
In the second case, cold dry snow, there is a lot of static electricity, but apparently there are differences in the anti-static material to use, depending on the state of the snow (fresh vs old) so that if you don't have the right formulation, you're better off not waxing.
This I can attest to. I've been to races on fresh dry cold snow where the skis waxed with cold race wax refused to glide.
Truly, you need to read the study and the response from Swix engineers to appreciate it.
The study is focused on XC skis, so not that applicable to alpine. Also, the guy used some weird methodology (like brushing the skis with a rotating steel brush, after waxing) that honestly make its results very questionable.
Second, he flat out found that even so, waxed skis are faster initially for up to a few kilometers.
My conclusion is that the "study" can be disregarded as being of little to no value to alpine ski racing.
The most basic explanation is that the sintered ski base has "pores" that wax flows into when pressed or flowing (heated).
Although you or I may describe these as "just pores", the reality is a little more complicated. Number one is that sintered plastic has "amorphous" regions where wax can be absorbed and this is (honestly weirdly) described as dissolving wax into the base, same way sugar dissolves into water.
Another aspect is that although the sintering process (compress and heat plastic molecules) creates a very dense structure, it is not as dense as a diamond crystal, so there are little spaces for wax to get into, here are some microscope images: