Soya and almond milk are the most popular of all the alternatives for a few reasons. They are commonly the more affordable of all of them, with the more expensive being cashew and hazelnut in some brands. Also soya milk is the most comparable to cow’s milk as it is the most ‘complete’ as a source of protein, fat and carbohydrates. All of these milks can also be sold in sweetened or unsweetened versions so can suit even more people’s lifestyles and diets. They can even be used as a treat as there are flavours to choose from like strawberry, vanilla and chocolate and this can make it interesting for kids too, if you’re trying to make the change as a family.
Here is an article stating pros and cons about six milks:
https://www.ecowatch.com/6-alternatives-to-milk-which-is-the-healthiest-1891128088.html
A huge amount of people are lactose intolerant/sensitive and don’t even know it or take it as seriously as they should if it is mild. This could be, in the long run, detrimental to your health if ignored, so why not try something new?