It is literally a cost they accounted for. What difference does it make if they are accounting for a $750m impairment loss or a $200m game development budget?
It’s a loss of book value. The cost was incurred when they aquired the company. This is simply an accounting change on the balance sheet if they were to ever sell the company again (this is what they think they company and IP are worth)
Book value can also increase in the future (if one of their games takes off)