If they are using a side chain they are using an alt-coin by another name
Agree and I haven't seen any proposals for how these are even going to be done well by altcoin standards. The proposals I've seen are merged mining and a closed group of block signers.
Absence of evidence is not evidence of absence.
We're only at the beginning of the beginning. Sidechains, CLTV, and two-way pegs are only the primitives and we have no more idea what may be possible with them than the inventors of the transistor could foresee the Sony AIBO and Girls Gone Bitcoin.