I don't think the new GFL will cost thousands of dollars in the future. A lot of new packs have been released, and these cards are never comparable in price to the old ones.
Selling beta cards seems like the right decision. In the future we will have to separate the battle formats and you will not be able to use the beta cards in the Modern format.
Well, the SPS stacking is also the right decision, as now the price of tokens is too low :)