Cardinal Arinze has nothing to worry about.
80% of current Mass attendees are at least 65 years old, with a bit of Arthritis (and a bit of weight) settling in. Liturgical dancers will be a dying breed thanks to the precipitous drop in younger church attendees.
Once the "smaller, purer" church as desired by BXVI, Opus Dei etc is realised, then there will be no one at Masses except the priest and a handful of ultra-conservatives.
Some of the flavour of Arinze can be discerned from his stating to the former (sacked) Bishop Bill Morris of Toowoomba that the Australian Church was too tolerant. (I imagine he would think that he would think the same of the U.S. church).
Arinze and his like-minded colleagues in the Roman Curia should be using their energies in addressing the catastrophic effect of the clerical abuse crisis. Instead they worry about liturgical dancers, and, in Arinze's case, whether or not to kneel at Communion. Talk about fiddling while Rome burns!