The idea behind RG is to find a new coarse-grained description of the spin system where one has “integrated out” short distance fluctuations.
Physics has lots of structure that is local. 'Averaging' over local structures can reveal higher level structures. On rereading I realized that the critical choice remains in the the way the RG is constructed. So the approach isn't as general as I initially imagined it to be.
An exact mapping between the Variational Renormalization Group and Deep Learning by Pankaj Mehta, David J. Schwab
To me this paper suggests that deep learning is an approach that could be made or is already conceptually general enough to learn everything there is to learn (assuming sufficient time and resources). Thus it could already be used as the base algorithm of a self-optimizing AGI.