Well yeah the 2020 halving is also 'priced in'. Everyone knows the economy behind Bitcoin production and inflation. Knowing from the start when halvings in production are taking place and having a cap on the total money supply is why many people are here and why many speculators forsee an increase in price over time as long as new money >= coins wishing to be sold.
Yes, nothing happened after the first halving when the price was $9 because it was priced in. Nothing happened soon after that. Can't fight science.
Explainable by demand (new money >= coins wishing to be sold), not
necessarily a direct result of the halving. The point being you still need new money coming in to be greater than the value of the coins wishing to be sold regardless of mining amount. Saying supply halving MUST mean price increase is not true.