Of course there are fundamental laws that establish the bounds for which the climate system can change from C02 forcing. The Clausius-Clapeyron equation fundamentally constrains the relationship between precipitation and evaporation. The mean position of the Hadley Cell is fundamentally constrained by the meridional energy gradient. There are many fundamental things about the climate that we know are happening and will happen and thus it is not surprising that climate models with all sorts of resolutions and configurations have overwhelmingly predicted basic principles like “wet gets wetter” in certain areas with high confidence.
I see where you are getting at over ongoing areas of research regarding how climate models handle regional-scale changes, concerns about coupling, ENSO, the MJO, etc. I’m not rejecting the importance of that but I think where we differ is that I would strongly assert that those are second order topics that won’t alter the first order changes that are constrained by basic physical laws. One of which is that the PNW wet season is going to get wetter as the planet warms. It doesn’t matter what happens in the maritime continent or anywhere else, that’s not going to be incorrect.
Yeah the general blobs of wetter and drier might move around a little bit based on the ongoing research…but fundamentally, no, it’s not going to flip the sign.