With ETFs buying significantly more BTC than is being produced, most BTC owners being HODLERs, and the halving being close, I doubt we will have a big dip. Maybe one or more minor dips, but I don't think BTC will ever again see prices anywhere near what we saw this summer.
Discussion
I think you're right.
Up forever? That would be nuts😄
Nuts, but possible. Even likely because of math.
The (new) supply will become increasingly constrained, but the effective supply (what people will sell or trade) can fluctuate, and the demand can fluctuate. There's no reason that decreasing new issuance must mathematically lead to ever-increasing price, even despite high fiat inflation.
There is such a small portion of the world's population that has BTC, that as more people buy in, the higher the price will go. The more the world's fiat currencies are deflated and the more the governments try to lock down electronic payments and bank accounts, the more benefit a person will get from BTC making them want it more. I don't foresee demand decreasing or even slowing the increase any time soon, but we will see.
Just don't bet your farm on it😉