Halving doesn't decrease the supply, halving just reduces the inflation, it decreases the amount of BTC being dumped on the market though, because miners won't be able to dump, if less ppl are selling and the same people are buying the buying vs selling shifts to the buying side, thus increasing the demand.

The halving can't be priced in because it's not a news, it's a shock in new supply being created, it's impossible to price-in imo.

Assuming all of this, sooner or later FOMO kicks in and fireworks happen, scarcity, less inflation, demand increasing, fireworks.

Just my 2 sats