Niko Neugebauer has some speculation regarding In-Memory OLTP:
In SQL Server 2019 without that much deserved fanfare (for me at least), Microsoft has released a couple of improvements that made me think about the current status (was apparently almost dead) and the future of the In-Memory OLTP technology, that was launched in the year 2014, and besides significant improvements in SQL Server 2016 looked pretty much abandoned since.
This is a perfect example of an excellent idea halfway implemented. There’s a lot of potential here, but enough pieces are missing that it’s hard to recommend using it outside of specialized scenarios. And that’s a shame given the potential.