I do like the snap concept, but some implementations are just not that great. For instance, kustomize as snap doesn't let you read anything outside that is not in the snap fs. Not even in --classic mode. A similar issue happens with nextcloud which is good on paper, but if you tweak something inside the snap fs it will be overridden in the next update(expected behavior); however, for services that require mutable configuration there needs to be a way to preserve that data (I tested that nextcloud behavior more than half a year ago).