With that being said, after a second thought on the situation, I strongly believe that difficulty has most likely hit the top, for now, starting from the next epoch my guess is that we start consolidating to the downside for a few months (unlike I thought a while earlier for many reasons which I will talk about in the near future), the correction won't be major so if you have an S9 and pay 5 cents per Khw, it's impossible for you to become profitable again, however, the adjustment will be a small push in profit, meanwhile, I wouldn't buy any mining gear at these current prices.
I waited a bit before replying to this, to see what the trend is at the end of the targeting period and not be completely off from the start. Even if things are not really going the way I expected I still stand on my previous assumption that we might still see an increase even with the insane ROI period and not a small one.
And this would happen not because your math is wrong or your reasoning but it might because by people who have not the same reasons, not the same plan, and are not making their plans on their own financial power.
One of the things that made me think mining will go the same way as shale, not really caring about today's prices or even the future is the news about
Core Scentific with their purchase of ~17 000 miners, those are companies that received funding from investors, they present a business plan, they fail, it's not their money they lose. In the shale industry there are hundred like these, not risking their own money and the 3rd mortgage on their house, these guys can keep buying and putting hashpower online even if it earns them pennies, not even talking about ever ROI.
With no serious price swings which would upset the balance too much, I would venture and say we're going to see at least 50% increase in hashrate based on the same price by the end of year.