Rock Werchter has always had a pretty diverse lineup. As mentioned before, in the last 10 years you've had Dua Lipa, Stormzy, Oscar and the Wolf, Pink, The Chainsmokers, Macklemore, Ellie Goulding, Pharrell Williams and more playing in prominent spots. I'm not sure you'd get them playing Download or Rock Im Park anytime soon.
I'm not sure this year represents such a radical change in direction or genre for Rock Werchter as you've suggested. We've only got maybe ~25% of the total lineup announced so far? This seems premature to be making statements bemoaning about how the festivals changed when we don't know what most the acts will be yet!
If you're interested in going to a more narrowly rock focused festival, then there are plenty of other festivals this summer catering to that market like Download, Rock Im Park, Rock For People, etc. I'm not sure Werchter is, or ever really has been, exclusively a rock festival in the same way as these other festivals mentioned above.
Aurora was tremendous on the park stage this year. We’ve been fans since we saw her as a teenager playing the Glasgow college of art in front of a few hundred folk, just before she released her first album. Seen her often since then including three at Glastonbury. Absolutely unique haunting voice.
good choice!