Every hiring manager I talked with shared how SO Jobs was the best place to reach developers. I reached out to a few people at StackOverflow to get a sense of why they are shutting down this product that did very well.
I didn't get real answers beyond "we don't think job boards are the future" which I don't fully buy, given the success on both the employer, and the candidate side. What might be the case is the growth in profit was not what Stack Overflow hoped for, and this is why they are retiring these parts.
My suspicion is that Stack Overflow expects to make 10x more revenue with enterprise branding services (effectively not allowing just job posting, but you need to buy a large package that has other things bundled that you need to get if you want to access something like this job board).
Note that with this change Stack Overflow effectively locks out all small and medium-sized businesses from working with them. Starting from the middle of 2021, I heard they were not onboarding companies with less than 1,000ish employees to the job board either.
It makes perfect financial sense for Stack Overflow, if they are indeed making the change to maximise revenue collected from employers. However, there will be a large gap on the market for startups, small and mid-size companies who will not qualify - and will not have the budget - for the "employee branding services" SO will keep providing (but does not share details on).
[1] https://twitter.com/GergelyOrosz/status/1457665269267116034?...