The original article is much more about end-user SaaS type cloud experiences than the IaaS or PaaS services you're mentioning. The nature of SaaS is that it is

The original article is much more about end-user SaaS type cloud experiences than the IaaS or PaaS services you're mentioning. The nature of SaaS is that it is directly facing the end-user. IaaS or PaaS services are more B2B style and so the customer and the end-user are not the same. The different nature of the SaaS beast doesn't mean that IaaS or PaaS systems are any less vulnerable to things going wrong (see the EBS outage earlier this year). But Iaas and PaaS providers are more vulnerable to customer loss if APIs change (due to the instantaneous breakage) than SaaS providers are if UIs change.