I’m not sure if you are aware, but there is an excess of nodes that are sitting in standby mode and getting paid node provider rewards at this time. This change to add the 60 new application subnets has no impact on ICP inflation and does not add any new node providers or nodes to the network. It simply puts idle nodes to work. It has an additional benefit of enabling performance based node provider rewards that is based on a higher population of active nodes for each node provider. That means there is an increased probability that inflation could go down for any node provider who cannot keep a higher percentage of their nodes in operation reliably.
This will not impact inflation since we have a large excess of nodes in standby mode and getting paid node provider rewards already. Notice that @alexu referenced using the networks spare capacity to handle the additional subnets. That means he is not proposing to add new nodes or node providers or inflation.