You are right, that's how it works. When you click others, it selects all values except the two top values, so you will see number 3 and 4 with the rest under the Others category.
I'm afraid this is how it works in Qlik Sense, What you could do is add the same dimension as 'Alternate Dimension' without the limitation. That way users can easily switch to the complete set of values.
Erik Wetterberg https://extendingqlik.upper88.com/