While the easy answer is to say "that's business" this thread has gotten so much activity that it's worth going over the details.
First, Cumulus did not have enough stations (like iHeart and Entercom) or a strong position with fewer stations (Like Emmis and SBS) to be particularly viable in New York City. They either had to grow, at great expense even if stations were available, or sell.
Second, Cumulus needs cash to make its debt manageable. Coming out of bankruptcy, they needed to spin some assets.
Third, WPLJ was in a revenue tailspin, off about 60% in the last 6 years alone.
Fourth, to improve revenue they'd have had to change format, which means a loss of current billing, and a loss of perhaps $10 to $12 million in the first year (from going to zero billings and having to build back up in a new format). Cumulus could not do that having just come out of bankruptcy.
Fifth, WPLJ had a format that was duplicated on another local station and "approximated" by several others in age appeal. Listeners are at no loss for OTA alternatives. But for much of the market area, many are getting a choice they did not have at all. So for listeners have gained, overall, from this change.
40 people did not lose their jobs. EMF has a small local staff, and they will obviously hire more people in Rocklin to handle increased donations. So, in all likelihood, the jobs are not lost, just moved to a different place.