That argument would be similar to mine if only 97% of people agreed upon the basic tenants of their religion.
Oh, now you suddenly accept the opinion of the unwashed masses?
I stated my reference as historical. If you transplant yourself back in the dark ages beneath 'God' chosen Kings and under the teaching of the approved clergy you'd find an extremely high consensus on basic tenants of their religion. You'd find all the same appeals to authority you have made.
When somebody questions carbon taxation as really being valid or not, consensus is not an appropriate retort.
When somebody questions the severity of future warming, consensus is not an appropriate retort.
Heck, when somebody questions if CO2 contributes to warming, consensus is not an appropriate retort.
The appropriate response in every case is to point to the evidence first. If the evidence is beyond the questioner, then fair enough to ask them to take it on trust in authority or spend a few years studying up. Just don't start pushing for making that appeal to authority the first resort because your walking down a road where even 'being right' might still leave you doing more harm than good in the long run.
We can declare with confidence that CO2 contributes, and back it up with evidence, so much less risk there. On the other hand if you go about proclaiming with certainty that 2050 will see catastrophic death, science has spoken, that's worse. If you go about proclaiming we are all doomed to that heat death unless we adopt 'measure whatever', that's worse still.
The trouble is you not only risk guessing wrong on the things we are still uncertain about, you taint all of the science by having made these prophecies upon it. Stick to the actual science and representing results appropriately, including the error bars and uncertainties. Leaving those out for expediency is a recipe for disaster.