But, it’s not. Alcohol is not a homogeneous mixture of two or more substances, nor a substance dissolved into another.
It’s its own chemical category of one or more hydroxyl groups bound to a saturated carbon atom.
No, because the alcohol in a drink (ethanol) is still not a solution.
That’s not the original meaning either. The original meaning came from Arabic for a stibnite distillation used as eye liner. It came from Al-kuhl. It’s the same way that “spirit” came to mean a hard liquor. Distilling something down to its purest form was meant to harness the “spirit” of the thing.
A given spirit is a solution of alcohol and water, but alcohol itself is not. Which makes the whole “technically” part of the joke fall flat.
100 % pure alcohol or Ethanol does not exist. It is always a mixture, specifically a solution, with water.