It can appear a bit counter intuitive because broadly alcohol is a depressant and cocaine's a stimulant.
The primary "risk" with polydrug abuse (especially uppers + downers) is that you end up taking much more than you would normally, and once the upper wears off, the downer depressed your breathing, pote being fatal.
But with coke + alcohol, even a "normal" quantity of both when combined is far worse. It's a bunch of heart signalling stuff that affects blood pressure and a few other things, in ways that really aren't good. Which is honestly pretty impressive because coke alone is an excellent way to fuck up your heart (credits, Rohin Francis/Medlife crisis, a cardiac surgeon on YouTube who posts way too less because presumably the stress of working for NHS isn't good for a doctor's health either.)
(Iirc alcohol and Tramadol are 2 things to typically never mix with other drugs; there's a matrix chart about drug interactions and these 2 are counter indicated with most other drugs. Weed, funnily and unsurprisingly, has one of the least interactions with other drugs.)
Haha...when I used to golf, 2 beers (American swill, no fancy high alcohol types) was the optimal amount. It was just enough to make me relax, which is so critical for a good golf swing.
I think that people feel that it's real, especially when under the effect. But I highly doubt its real efficiency, and especially its sustainability on long term.
Though both of them can combine for a very interesting experience, or so I've heard...
(Nerd snipe: cocethelyne is uniquely cardiotoxic, and is somehow even worse than cocaine. Even amphetamine salts are "healthier".)