Sony's been working on this for years rather than waiting for later NVMe standards to enable it with a generic solution
NVMe 1.4 has some useful features, but all they really need is add support for LBA sector size that matches the physical write page size (8 to 32KB), which should improve read speeds.
This should be possible on every NVMe 1.x device through the "Identify - LBA Format" command, which produces a list of preferred LBA sector sizes, ranked according to their perfomance. The sector size field, 'LBA Data Size (LBADS)', is a 7-bit value that encodes the exponent of a power of two (i.e. 2^N) - this allows a practical range of 512B (2^9) to 16MB (2^24),
and up to 2^128 bytes, which they don't yet have a binary prefix for.
A custom flash-aware file system, which uses write-once logic to reduce write amplification, seemed like a great idea back in early 2000s - unfortunately, all research papers that I've read so far conclude that flash-aware filesystems perform
worse in real-world workloads than legacy hard-disk based filesystems, because current SSDs implement very efficient background garbage collection.
This could probably work if Sony made a breakthrough in performing garbage collection on the OS level, and devised an allocation strategy that would align all writes to the size of the erase block (typically 1-2MB).
I'd rather say they simply need to fine-tune their APIs and applications to the more effective usage patterns of NVMe SSDs - that is, schedule deep IO batches with large block sizes, and avoid unnecessary buffering and data copying by taking full advantage of their reduced access times and enormous read bandwidth.
Microsoft has its own rssd with hardware bitlocker software on it. You can't change out the rssd without using special software to swap them.
What you refer to as 'hardware bitlocker' is the
'Encrypted Hard Drive' mode that uses the AES256 hardware encryption and TCG OPAL authentification in the hard drive. This capability
was introduced in 2011 for Windows 8/Server 2012 and is currently available in many SATA and NVMe SSDs, and these drives
can be managed by either BItLocker GUI or console commands.