Let's image we put a ban in place to prevent this revolving door. Why would someone working in the industry be willing to forfeit their post-government career, especially if they are a political appointee and might only have the role for a few years until the next election?
That is a huge disincentive to participate in governing and will likely lead to more career politicians and bureaucrats which isn't exactly an ideal situation.
Private and public sector employees could collaborate where it makes sense, just like companies sometimes collaborate on shared initiatives like working groups or open source projects.
Government can actually work better than it does in the US -- as it does in other countries -- but one must first accept the ideological premise, which seems to be what holds the country back.
That sounds great in theory, but the problem is that many of these leadership roles if not elected directly are nominated by the president and therefore they are political in nature and those politics can flow down through the organization.
For example the FCC chairman, Ajit Pai, is resigning this week. Would he have resigned if Trump was reelected or would he have been re-upped for another term? Is Biden obligated to find this Republican a job somewhere else in his administration? Is Pai just supposed to retire at 48 years old? Can he go back to working for Verizon like he did for a period earlier in career? How many other people at the FCC have or soon will leave the agency due to the change in leadership?
That could be changed though. It's not how it works here in the UK. The ministers in charge of departments are political appointments, but we also have a substantial politically neutral civil service with lots of headroom for career advancement. (politically neutral to the point that you are not allowed to publically express your political opinions - posting them on social media could be a firing offence)