Was "the modern cocktail" intended to mask the foul taste of Prohibition-era liquor?

Question

I have long suspected that what we know today as a "cocktail" was invented to mask the taste of bad liquor. Indeed I've found several unsupported assertions to this effect online, generally pointing to an alleged Prohibition-era ruse (sweet ingredients, very cold temperature, fancy glass, adornments, etc.) to hide the awful taste of much bootleg gin. I'm interested in locating some researched/documented support for all this.

Answer 1

What do you mean by modern? The first known written mention of a cocktail in the US is from 1803, well before Prohibition. It's possible that during Prohibition those flavors were accented more, or that in general cocktails have been masking the taste of alcohol from the beginning by design.