A significant round of layoffs forecast last month at WarnerMedia is getting under way today. CEO Jason Kilar emailed staffers this morning, acknowledging the process is “painful” but also calling it a “critical” step in the AT&T division’s evolution. (See his full memo below.) The entertainment outfit has seen multiple staff reductions since the acquisition of Time Warner closed in 2018. Historically, its three main units — HBO, Warner Bros and Turner — operated as mostly autonomous groups. Now, synergy is the mission, with teams being blended for the first time in decades and a lot of positions eliminated in...