That is a rather cynical take. More pragmatically, while it may be true that companies don't immediately jump at the opportunity to export in a common format (or there may be too many standards to export as), there is suddenly a market for data adapters if the companies do not import from their competitors, and a missing feature on a product sheet in any case.
If it's any sort of bigger service, competing services will implement their special format.
If they frequently change this format to break those implementations or clearly make it much more complex than it needs to be, that can also have legal repercussions.
the data will be useless other than as a source of information. If you have data for an online vector editor, the vector data can be legally taken out via a common format (such as json), but there'll be no importers for this shape of data.
Any business can easily construe a common machine readable format that's also completely custom, and unimportable anywhere else, to satisfy the letter of the law.