Maybe they are trying to reposition as a credentialing institution, where people can network, build skills, and manage their professional calendars.
I am not sure if this is the case here, but numerous acquisitions outside of core competencies could point to a strategic shift in positioning, possibly in an effort to shore up declining revenue and relevancy in the core business.
1. Social networks seem to decline over time as newer alternatives or substitutes arise. Specifically, it seems LinkedIn is not as strong as it once was, and growth can no longer be sustained on the percentage basis.
2. Generally, a company that has amazing product market fit and strong growth in an offering would reinvest the lion-share of capital back into the business.
I don't purport to know what is the case here, just providing the counterpoint.
Perhaps similar to how while Google acquires all sorts of interesting startups, it doesn't mean they're shifting away from search/ads.
IT recruiters seem to be looking at candidate's github profile, while I haven't seen anybody asking for a linkedin profile.
Sure, there's lots of other areas besides IT, but if IT has moved to something more specialized, I expect a similar trend for other areas.