Indeed there are many things in hiring that are actually broken. The entire system did not change a little in the past 20+ years. And now, there is a trend to automate those dysfunctional recruitment processes, which makes them even more dysfunctional. When looking for a job in the past, you sent a CV to the recruiter. Now you apply for a job via an app, where you retype your CV. Each app wants you to create an account. Each sends you tons of spam. If two companies are using the same platform it sometimes prevents you to apply, because your email is "already taken." Many apps are very slow, poor from a UX perspective, and even from an engineering one. And this all is only a fraction of all the hassle people looking for a new job are facing.
You have mentioned an interesting perspective of partial switching and risks on the engineer and organizational sides. I think these risks are also signs of obsolete thinking about recruitment as such in some way. That is why it triggers "the solutions" of the wrong problems, like creating those recruitment automation platforms.
I want to cultivate recruitment a bit. I have created a short training program to help recruiters design a better hiring process. More you can find here: https://bit.ly/3nwVlHG
I think modern organizations must learn to organize work around people and attract the best available talent from anywhere. Remote work makes it easier in some ways. I see hiring as a collective sport for many people inside of an organization. Especially for those who believed that they are not part of the hiring process. It requires different management practices, different onboarding, and also getting rid of stereotypes (eg. why somebody has 3 months "unexplained" break in her CV; or why does somebody prefer only partial assignment like 3 days a week; crazy requirements like poor job descriptions often assembling 4-5 separate jobs into one; obstructing career change, or simply treating an employee like just a resource - ridiculous in the era of knowledge-intensive organization).
I am not sure whether multi-round testing of engineers for skills is of any value. Hard skills one can learn. Often quite fast if there is an onboarding process available. Culture fit is what matters, and it is what candidates can't test at all.