I remember the balloons received negative reaction initially, I have memories of a mock up balloon flying across the screen constantly during an episode of Points of View getting in the way. Due to the fact that up to that point BBC1 idents had been a single silent logo, it's no wonder folks in Tunbridge Wells were slightly shocked. Everyone came to love them though.
Looking back the dancers weren't that bad, just that they replaced the balloons, meaning they were on a hiding to nothing. The ITV celeb idents faced a similar fate. At least they were well produced with a colour scheme, post production, identifiable well produced music etc etc. The Queen Mother passing away 2 days in didn't help.
But these have no positive qualities. No music, no production, just a static shot. They make ITV's look like the best idents ever. They look like something you might have got on Living TV not on BBC One!
The business about it being just for 2017 I would take with a pinch of salt, they'll last as long as they want them to last.