I think it's safe to say that most people who've considered the issue think that a doctoral degree in the sciences and engineering in the US often takes too long.
How long? According to the latest data (see here, Table 1-12), the median time to degree in the physical sciences, for example, is 5.7 years after starting the program, while in all of engineering it's 5.3 years.
Too long for what? Well, life, basically. Any decision to go to grad school is inherently a trade-off with opportunity costs. Graduate stipends remain low compared to expected wages in entry-level (bachelors degree-qualified) positions in the sciences and engineering in industry. The long duration of doctoral programs is certainly a powerful disincentive for many who might be interested but are under financial pressures. Family considerations are also a major factor. From the perspective of basically any career path, thanks to the time value of money and ideas of seniority, it's better to get going earlier if you have the qualifications for the particular job. Companies would rather higher younger (cheaper) people.
So, there are already strong reasons to think about shortening doctoral programs. Now, with the proposed change in duration of status of student visas (rule here, with plenty of editorializing; legal challenges very likely forthcoming in September) to four years, there is additional pressure.
Why do US programs take so long? Don't they give PhDs in three years in the UK and Europe? In the UK and Europe, a student enters a doctoral programsafter already pursuing and receiving a masters degree, with grad level coursework taking place there. Thus they go directly into research. In the US, in contrast, it is far more common for students to go directly into the doctoral program. Likewise, in the US, it is far more common for funding for students to go through PI-written research proposals, while in the UK, the students come funded, so to speak.
Enter a new pilot program from NSF, the UIDP [University Industry Demonstrated Partnership] Industry-Integrated PhD Scholars Program (I-PhD). The idea is to shorten the doctorate to four years, with at least one of those years on-site at a company. As the announcement says, "Students' first year of funding will be provided by their universities, with the remaining years covered by NSF. Industry partners will provide matching commitments to cover at least one year of practical experience conducting dissertation research at a company site. Students will be co-advised by academic and industry mentors, equipping them with critical skills for their future careers." The initial plan is $47M over five years, and there will be a webinar (see here) next week about this. (Up front, I do want to disagree with the framing that existing PhD programs are geared exclusively for academic careers. It's well established that the fraction of PhDs in the sciences and engineering who go on to become faculty is low, and most go into industry. Faculty PIs know this. Students know this. The problem solving and analytical skills taught in doctoral programs remain highly valued outside academia, at least until AI replaces us all.)
This is certainly very interesting pilot program. There are rumors that the DOE Genesis Mission is going to put something extremely similar in place as well. The implementation details will be enormously important. (For example: Who is eligible? Who handles the coordination between industry and the university - that is, who does the match-making and how? At the department-company level and at the particular academic/industrial advisor level? How will intellectual property be handled? Publications? Project design? If there are economic challenges, how committed are the companies?) Given that this is a form of NSF fellowship, it seems highly likely that it will only be open to US citizens and permanent residents. Obviously, not every discipline is well-suited to this, in terms of there being a ready supply of companies set to buy in. Still, it is absolutely worth seeing how this works.