There will always be miners that find profit. If some miners leave, then the difficulty goes down and the system self adjusts itself to provide profit for other people. There will always be a clear incentive for some people to keep mining. As the price goes up, the deflation progress will not be a problem.
Actually if too many miners leave during a short period (less than 2 weeks) the network will have a hard time until the adjustment time comes.
Of course, the chance for that is small.
If the price continues to go up, then indeed the miners will stay. At least until the next halving we are safe with the current price range.
Halvings don't make the price go up. Correlation does not mean causation.
Last time the halving coincided with bitcoin being discovered by the mainstream press. And Cyprus happened when they confiscated people's savings in a bail-in for the banks.
There is no big news to bump up bitcoin this time. It's the opposite - Brexit is a victory for the people, it makes Britain safer as EU rules like confiscating people's savings no longer apply.
I have the same thought, the halvings don't have a total control of the price.
And I doubt the price will have a big up in a long term, maybe a good alt can make the bitcoin price stay low...
If this stands true for the next halvings too, then I fear for Bitcoin's future.
For the last halving there was quite a rise in the price about half a year (I didn't research exactly) before the halving, a rise that allowed miners to cover their costs even after halving.