IPCC energy budget logic and then the real World, page-159

Google something like "have winters been milder due to climate change". They have. Warming caused instability in the jetstream has created some severe cold snaps, but that doesn't negate that winters overall have been warmer. Plus heavier snow falls are a consequence of a warmer atmosphere holding more moisture, and warm air streams flowing into cold fronts.

Predictions depend on actual CO2 emissions. So I don't see why you would not accept correcting model inputs for actual emissions. We learn what will happen for a range of emission levels. But if you want to check accuracy of models you must accurately include the specific emission levels.

And you also need to adjust for the occurrence of shorter term natural disruptors to trend - such as large volcanic eruptions and waxing and waning of solar output, the exact timing of which isn't predictable. Those variables affect things short term, but underlying warming trend remains. Correct for those unpredictable short term natural climate variability factors and for actual CO2 emissions and models have been accurate.

We'd like greater regional long term trend clarity, but that's not to say that useful guidance for regional planners isn't available.