LEGO is a toy company, who benefit from their toys being collectible, but in the end want to sell toys. Yes, they are re-releasing some "classics", but only those which they think will have immediate, broad appeal and will sell past their production targets. I doubt they will start re-releasing more obscure sets as mentioned before.
SW is hot right now, and unless LEGO has a commitment to resellers (which they don't) they would be stupid not to cash in and release a flagship set based on the flagship of the franchise.
I often get the impression many of us here think LEGO is making short-sighted decisions, but I don't think they do. They have obviously factored all aspects of their appeal (both to kids and adults) into their product development, plus they are obviously aware of their status as a collectible product, and have many examples from other brands to look at and learn from. If LEGO thinks the time is right to make another MF UCS, I bet they have data to support it will sell well (compared with their targets).
The "old" MF UCS will still have value, after all, it was the holy grail for so long, and if you collect you need that one. There might be a small bubble popping for those who bought at $2-$3k with the intent to resell, but for those who bought at retail there remains a nice amount of profit (granted, smeared out over many years) to be had.
And if anything, the next holy grail is already out there, be it Taj Mahal, Grand Caroussel (though rumors on its replacement are also swirling), Green Grocer, etc.
The thing is, the more people sour on investing in the larger sets (which is what I sense is happening right now), the more likely it is that in 5 years from now one of the currently retiring sets is the next UCS MF. Especially if TLG has to downsize their portfolio since the whole TLM surge in popularity is by now gone - some sets just won't be made again for a long time.
Net, this is not the end of the road, just another inevitable change in the marketplace. Adapt or else ....