Some details on the Swiss side:

There are two variations of the B permit one can get. An unrestricted B permit isn't tied to a specific employer and provides a path toward permanent residence (C permit) within five years for EU citizens or ten years for non-EU citizens. Based on my experience, EU citizens almost always get an unrestricted permit and are treated relatively well by the immigration process: at their first application, they receive a five-year B permit, and at the first renewal five years later, they automatically get a C permit. As a EU citizen you just need to find a job, and your right to work is essentially unrestricted.

The non-EU path is quite different. A non-EU citizen only gets an unrestricted B permit if they prove they have special skills that are not currently available on the local job market. There is a yearly quota for such permits. One can also be unlucky and get an L permit, which is for temporary work only. Moreover, restricted B requires yearly renewal with a demonstration of ongoing employment at each renewal.

If you get a restricted B permit (or L), you don't have any direct path to a C permit, no matter how many years you've lived in Switzerland. You can complete your bachelor's, master's, and PhD degrees and continue working for a university as a contractor afterward, and still not be eligible for the path toward a C permit after over a decade of living in the country. To get a C permit, the last two years prior to the application must have been on an unrestricted B permit, working a full-time, unlimited-term job contract. The change to an unrestricted B permit requires you to have become a "special talent" during those prior years; otherwise, it won't be granted.