This is interesting and important to know about but increasingly I feel like stochastic uncertainty isn't the main source of "random/error variance", it's more

This is interesting and important to know about but increasingly I feel like stochastic uncertainty isn't the main source of "random/error variance", it's more like real but uninteresting heterogeneity. I can see using this in practice but it's probably a minor part of the whole picture. I don't mean to sound dismissive; I think it's more that I wish there was more focus on other types of uncertainty as well.