The problem is how lucrative it is. If they were the only ones on the market with it they'd probably make a killing... But how big is the diesel market? Might not be worth it to a business.
This is why open source is so much better for small markets. Get one capable person with a hairbrained idea to run with it and we could have so many options opened up.
I wrote the code to provide anti-lag, rotational idle, displacement on demand, lean cruise/idle, 4 drive mode switching on the fly, hard ecu reset, a code based injector kill switch and so much more on an oem WRX computer.
Imagine if I ported it to our cars.