Season 7 finally had Bran and Sam comfirm a long-held fan theory that Rhaegar Targaryen and Lyanna Stark were in love and eloped, and that their baby – that'd be Jon – is actually a legitimate Targaryen. Jon will learn the truth probably in the first or second episode of Season 8, but with the Night King approaching it doesn't leave a lot of time to deal with the implications which, for Jon, are world-shaking. Not only is his identity tied up in Ned Stark, he has also just fallen in love with Daenerys, his biological aunt. After so many seasons of build up, it's important the story allows enough breathing room for the consequences of this reveal to really be felt. It can't all be battles, right?