Dont think they looked at that timeline blizzard posted nor have they regarded the fact that blizzard stopped allowing paid transfer on Era not long after turning off the clone services that people used.
OP thinks its money on the table, but is ignorring logic and facts presented here in his own thread.
one of the very compelling reasons you are likely wrong is as Xfour said about the TBC micro transactions. If they allow you to leave Anniversary then they are throwing out potential MTX.