It's not really a book about 'best practices', despite the name. It's more like an encyclopaedia, covering every approach out there, putting them in context, linking to copious reference papers, and talking about their properties on a very conceptual and practical level. It's not really like 'hey use this database vendor!!!'.
Most of that research is decades old. I specifically remember Lamport timestamps. Not only has that held up, it's unlikely to go anywhere anytime soon. Most topics covered are as fundamental as the two generals problem; almost philosophical.
No database vendor can solve the issues around two concurrently existing write masters. Sync will be necessary, conflicts will occur. A concrete vendor could only hope to make that less painful (CRDTs for automatic conflict resolution, ...). That's kind of the level that book operates at.
A year of two ago I read Ralph Kimball’s seminal The Data Warehouse Toolkit. While I could see why it’s still often recommended, it was showing its age in many ways (though a fair bit older than DDIA). It felt like a mix of best practices and dated advice, but it was hard to tell for certain what was what.