It's good advice to not take shots after you're already drinking.
Even for mixed drinks, the ABV can vary a lot more compared to lagers, pilsners, etc. The sugar content can be quite a bit higher in mixed drinks as well.
since both beer and wine differ, both in alcohol and sugar/carbohydrate contents, it's not all the same. Also high spirit liquor(37%+) is very different than wine (sub 14.5%).
A large part of the hangover is the dehydration which depends on both alcohol and sugars; as a general rule you want more water.
Even for mixed drinks, the ABV can vary a lot more compared to lagers, pilsners, etc. The sugar content can be quite a bit higher in mixed drinks as well.