This seems like an easy way for money and stuff to start going "missing". One has to remember that many large companies don't have an in-house set of software

This seems like an easy way for money and stuff to start going "missing". One has to remember that many large companies don't have an in-house set of software engineers to kludge things together, or a set of people to audit and make sure problems aren't accumulating silently somewhere because of some bug or some vendor changing their API or whatever. Even if they did, the supposedly "agile" solution proposed here just sounds rather fragile. You even see this in codebases that are built on a "microservices" mindset -- you start getting weird emergent patterns in internal dependencies that start bogging things down. For a smaller or even medium-sized business, sure, maybe a custom solution works. But it looks like for the scale of organization SAP works on, it seems difficult for an individual to even understand all the components of that organization, let alone build something maintainable for themselves and their eventual replacements.