I'm not as familiar with Oracle, but surely it is providing significant benefits or large organizations would be dumping it and running to more reliable alternatives. These time estimates are also not very pertinent to the actual running of a large database. Nor do they speak to the various technical problems one has when running a big db that is mission critical.

Lots of the classic hn "how can they be so stupid?" comments. Give the cto's more credit. Just because you write JavaScript and used mongodb once does not make you an expert on Oracle or running a very large business.