Some really nice detective work on the chip capacity, I think we could get an idea on how much it can grow if all the stars align, but what it is possible without that, is something different we can only guess.
Probably the outcome will not change even with a bidding war as I don't think bitmain and the others have a real chance, revenue for miners might have quadrupled, expenses barely went up for the same portion of reward and they could also pass an increase in chip price to the demanding customers. Can bitmain raise the price by 1000$? it will sell all the gear on pre-order with no problem, while I doubt Xiaomi would afford to pass to the consumer even a 10$ price increase. But in the end, even if they could win a price war I doubt they will win a negotiation war, there is a trade war going on, there is a change of power in the US and nobody has a clue he things will go so I doubt not only TMSC but others too will nor risk to drop longterm clients for a Chinese company that tomorrow might not be here.
That being said, I doubt also we will see anywhere soon a 2x, but, I don't doubt we will get there in the end. And even to the 4x.

(me and my predictions)
With the being said, there might come times when bitcoin holders will need to mine for no profit just to keep the blockchain running the way it is, sort of like how many people run full nodes now without any financial benefits, but I guess it's too early to judge since we don't know how will the mining fees become like since they will be more important than the block reward soon.
This was of my theories too, in the end in order to protect a trillion in assets large bagholder will need to subsidize mining in order to keep the chain secure, but how this will affect decentralization and what war for control it might trigger, paints a really ugly picture, but we're far from that right now, fortunately or unfortunately, god knows which.
Meanwhile, we're heading for:
Latest Block: 665248 (4 minutes ago)
Next Difficulty Change: between +11.1427% and +11.1456%
Just 4 hours to go so this will be for the start of the year.
As for what's coming next, if we go another 11% or we drop -5% it wouldn't amaze me one bit! +25% or minus 10%, that's another story.