The cost and emissions on the newer ones is out of hand, but I don’t think you have much of an argument that diesels have been ruined by technology.
I’ve owned a ‘94 GM 6.5, 96 Ford 7.3, 02 Cummins, 07 Dmax, 06 Ford 6.0, 11 Ford 6.7 and currently have a 20 Ford 6.7 and you couldn’t give me one...