The problems around data are in general harder to address than the processing part. Most people dabbling in software engineering don't have the skills or attention span to work on those, and most of the issues are already solved by extremely complicated systems (e.g. DBs, Apache projects, ...).

As for 12 factor principles, it was first touted by a PaaS provider. The whole idea is that they take care of the nitty gritty, while you can focus on the exciting (and technically easier) parts of software systems.