Earlier quoted context omitted.
By just about any measure alcohol is a "harder" drug than marijuana but certainly more broadly acceptable.
Having never done weed, if I smoke one will I preform worse at cognitive tasks than I would if I had a beer? I know, comparing uppers and downers, not the same effects, etc.
Definitely cognitive tasks would be considered more impaired by weed than beer, at "roughly equivalent to a pint" level. Likely neither would be a big deal.
Weed is neither upper, nor downer really, it an hallucinogen.
That means less ordered thinking. Quite possibly an increase in creativity and lateral concept matching (say, making or appreciating witty comments) but also an impairment to short term memory and direct logical reasoning.
For motor skills and reaction times, beer definitely hits harder.