Yeah but few people do that because building massive infrastructure on top of EC2 instead of using Amazon's managed alternatives is a great way to lose money, not just on the AWS bill itself but also on needless additional work for your architects.
Defeating vendor lock-in requires the development of sound cloud-resource primitives, and probably some regulation on part of government to not pay egress costs when switching to a competitor (since the high cost of moving your data to another cloud is anti-competitive). But nobody has come up with decent primitives because, you know, if AmaGooSoft don't need multi-cloud architectures for high availability, then why do you think you do? And government won't step in because none of the regulators understand how any of this works.
Defeating vendor lock-in requires the development of sound cloud-resource primitives, and probably some regulation on part of government to not pay egress costs when switching to a competitor (since the high cost of moving your data to another cloud is anti-competitive). But nobody has come up with decent primitives because, you know, if AmaGooSoft don't need multi-cloud architectures for high availability, then why do you think you do? And government won't step in because none of the regulators understand how any of this works.