Perhaps is the cerebellum "not critical" because the cortex is flexible enough to perform cerebellum functions if it fails? In any case DCN seem to be a fundamental piece to understand language. For example, the degree of success of Auditory Brain-Steam Implants (ABI) in children is really low  (ABI are done when coclhear implants are not possible due to lack/damage un the of auditory nerve or cochlea)
The dendritic tree connectivity of Purkinje cells is really massive. Seems to be some sort of bus (each input bit can be combined really a lot of state signals [such as the cortex prediction, body position, etc...]). Pyramidal cells seems to be more like a point-to-point network. For this kind of problem (all-to-all) is more efficient to use a bus. For example, many super computers (such as the BlueGene) have a point-to-point network for regular communication and a bus alike (a tree) for broadcast communications.
Certainly language (ASR) is really interesting but hard. Just to map different speakers phonemes over the same set of columns is a though problem
 E. P. Wilkinson et al., “Initial Results of a Safety and Feasibility Study of Auditory Brainstem Implantation in Congenitally Deaf Children,” Otol. Neurotol., vol. 38, no. December, pp. 121–220, 2016.