The last time we went through the halving not much happened at first but then after a few months we began to see the price slowly growing, this is because while both supply and demand affect the market they do not do it in the same way, a spike in the demand will make the price to go up immediately but a reduction in the supply is not felt in the market that quickly so prices tend to move more slowly, so I have the tendency to think the same will happen the next time the block reward is halved.