It's not just gamblers and traders that monitor market price, you can also monitor market price while applying your DCA approach. Remember DCA is simply buying accumulatively at different prices. So to get the best price offer while applying your DCA strategy you still need to monitor the market, look out for nice setup that is for experienced investors who understands what controls the market technically and fundamentally.
For a complete beginner or a novice they don't need to bother themselves with all this technicalities all they just need to do is buy at every new price but they should pay attention to the direction of the market if it is consistently buying or selling to know in what direction they should buy so they don't end up buying too high when they would have gotten it much more cheaper if they have had a little patience.
I disagree with you. You dont have to monitor the market at all times when you are DCA. There is nothing like the best price when you are DCA, at every single time you DCA you buy at the current price waiting to buy on the price you refer to as better price is simply timing the price because what if you did not get to see Bitcoin go to that price you wont buy until it is in that price. Now how does that get to be DCA when indirectly you are similarly practicing trading by timing the market.
For better understanding. Let me make it clear here. Ones an investor deviate from buying at current price when they DCA to waiting for better price opportunity which may not likely come then he is not using DCA anymore. Dont confuse yourself with this.