That was likely part of a carefully planned PR move. Microsoft was in a position to be able to weather a massive layoff, especially if it was spun as reducing duplication after picking up a new division. Nokia, on the other hand, would have looked far worse selling off half the company after a huge layoff.
Nokia, in many ways, was the pioneer of SaaS. They developed a globally recognized product that would become both the iconic application associated with early cellphone applications and paved the way for a globally distributed market for mobile gaming.
However, as time went on while using the product, it became increasingly difficult to find room to move horizontally as well as vertically within the space. Ultimately, continually completing objectives made it more difficult to pivot.
Inevitably, their SaaS product became frustrating and deprecated and the marginal utility diminished. With a lack of new offerings Nokia was forced out of the market it created (Snake as a Service) and we were forced to go back to playing the helicopter game on the bewest RIM blackberry.
I never saw them involved in the service business at all, to me they were a hardware company and nothing else. That's how I look at my phone (and computers too), as pieces of hardware not tied to any particular service or eco-system unless I decide they should be. I don't buy subsidized phones with a 'plan' and what software comes with the computer I buy is wiped out before it even gets run once.