Indeed, "we have evolved to be able to do something, but other species did not, so we should not do it neither" is a very backward argument.
Also, there is a whole spectrum to it. You don't have to be 100% medically diagnosed as lactose intolerant, it might cause you ocasional digestive issues without you even know it.
Like those unexplained, once a month or once every 3 months diarrheas that many of us take as a fact of life, it's actually not normal and might very well be dairy that is causing it for a lot of people.
At least, a lot of us do it a lot worst than we realize, and there are a ton of people with recurring mild digestive issues which should not be consuming dairy daily at all, but keep doing do due to the public perception that its a healthy thing to do when in fact it's not.
The ones that can digest it, do it usually less well than they think they do. Mild chronic diarrhea is prevalent is western countries, and a degree of dairy intolerance could very well be one of the factors.
It gets worse for most people with age, as elderly people can become lactose intolerant, fully or only slightly. This does not happen overnight, its a progressive thing, many people gradually stop being able to properly digest dairy.
There are also lots of dairy products that contain little lactose, from lactose-free milk to cheese. And of course, it's pretty simple to just take lactase pills.
From a completely subjective perspective, dairy products are some of the tastiest foods, and they're objectively a huge part of food culture in Europe. I don't foresee them going away.
But there is this perception that they are absolutely essential due to decades of dairy industry advertising and lobbying, and it's simply not true.