> The study compares a percentage increase of solar power against an absolute decrease of CO2 emissions.

local CO2 emissions. This has not affected pumping of oil, and since we aren't even able to store much oil, that means it's getting burned. That makes it clear the global effect must be very close to zero. And for CO2, only global matters.

You're essentially arguing that reducing demand won't reduce supply. It may not do so immediately, but certainly over time it will.

For example, there are oil fields that are unexploited because they would not be profitable. If demand rose, prices would rise and new wells would be opened. The reverse is also true.