Out of curiosity, what problem did you have that this approach solves?
Thinking about diffs, plain text diffs are typically compressed for transport anyway, so you end up with something that's human readable at the point of generation and application (where the storage/processing cost associated with legibility is basically insignificant) while being highly compressed during transport (where legibility is irrelevant and no processing beyond copying bits is necessary).
We have a JSON data store at Sanity.io where you update your data by sending in a transaction script which is at a quite high level ("increment karma by 5"). While these scripts explain your intention well, they are a bit of a hassle to work with internally since the language is so rich. We therefore wanted (what we've called) an effect format. The effect format would explain what actually happened when applying the transaction: "Set karma to 183". Mendoza is what we ended up with. The Mendoza patches are much easier to work with from a decoder's point of view.
As a side effect, we've also been able to use the Mendoza format for tracking changes in documents. The JavaScript implementation supports replaying the patches while maintaining information about where each part of the document was introduced. We use this in our Review Changes feature so that you're able to see exactly who introduced a change (in a JSON document!): https://www.sanity.io/blog/review-changes
Thinking about diffs, plain text diffs are typically compressed for transport anyway, so you end up with something that's human readable at the point of generation and application (where the storage/processing cost associated with legibility is basically insignificant) while being highly compressed during transport (where legibility is irrelevant and no processing beyond copying bits is necessary).