TLDR: It trains you in both technical and soft skills (technical writing, meeting management, etc.), and lets you gain experience with small and large industry projects, using different technologies. It essentially compresses multiple years of industry experience into two.
There seems to be a lot of confusion about what the program actually is. The Professional Doctorate in Engineering (PDEng) programs offered at Dutch universities have more in common with industry traineeships than with a traditional academic doctorate. As such, most of the negative effects of a PhD on job propspects (trouble actually writing code, far less job experience, etc.) simply do not apply.
For example, Eindhoven University of Technology describes their Software Technology PDEng program as follows.
The Software Technology program is designed to prepare you for an industrial career as a technological designer, and later on as a software or system architect. It starts with 15 months of advanced training and education, including 4 small, industry driven training projects, followed by a major design project of nine months in a company.
The program is specifically designed to teach MSc students with a good grasp of the theory how to efficiently apply that theory to practical applications. It is presented as a way to "fast-track" your career by gaining a lot of cross-disciplinary experience in only two years.
They write the following about their graduates:
The Software Technology program has been around for more than 25 years and to date trained more than 370 technological designers. Most designers have joined the companies where they carried out their design assignments and many now fulfill a management position.
Their alumni association XOOTIC released a detailed survey (pages 25-28), stating
Having a job as an XOOTIC is still easy: only
1% of the XOOTIC’s is unemployed. [...]
By far the most XOOTIC’s have an indefinite contract
The OOTI program is known in the industry according
to 80% of the answers and is rewarded
according to 44% of the respondents.
XOOTIC’s, considering what they know now,
would still do the OOTI program (96.7%).