What's Marvel playing at?

Because it's what they've been doing. They've been hinting at deaths and the departure of certain characters for a long time. Then IW went for shock value by killing off a bunch of characters. They can't walk all of that back now.

You also have to look at it from a practical standpoint. Comic books can add and drop characters whenever and wherever they want. Movies need actors and actors need money. Marvel isn't going to pay for a bunch of new contracts just so someone that died in an earlier movie can come back. Maybe one or two, but not all of them.