If you observe well, you will comprehend that some people don't want to purchase bitcoins when the price is on the decrease state, but when the price increase they will be interested to purchase, it's few people who do embrace purchasing bitcoin when the price is low, because all the new crypto investors do think that since the price is on the state of decreasing when they purchase it will go more down than their expectation.
But if they know that the bitcoin price is not going down forever and the price has the potential to recover after some time, then they might buy. I'm sure day traders/scalpers might prefer to wait for the market to recover rather than buy dips, but if they understand some of the opportunities that can be exploited to make a profit then I believe buying is the best thing.
But all of us have our own strategies and beliefs when trading, so we shouldn't be the same because we each have our share. I just want to say that the buy on dip is a good strategy if the trader or investor knows how the bitcoin market works.