I think both your examples speak to why we shouldn't be flippant about claims of climate collapse.

The Doomsday Clock is not a valid representation of scientific consensus, and is completely incomparable to the current conversation. It largely reflects the political interpretation of one non-profit. In contrast the concerns over climate change are not posted in PR briefs, but in a plethora of scientific papers, in various fields, that repeatedly show we are in or past a worse case prediction.

The ozone layer is more analogous, but the problem had the advantage of being a specific problem, with a soon found and cost efficient solution. In comparison, climate change is also 100% true, but rather than a particular aerosol that can be swapped out, it is literally the foundation of the entirety of human industrialization.