Sure there is a bit of a presumption of lump sum with that hodl camp chart, since each time you look at an entry date for a supposed BTC purchase, then you are able to see how that specific purchase did with the passage of time.
There likely is nothing wrong with having information about how purchases that we made on specific dates might play out with the passage of time, yet frequently, with the passage of time, we are likely going to end up with a variety of purchases with various costs and various amounts of BTC purchased, so the total quantity of BTC that we have is going to have various ways to assess how the totality might compare to the various individual parts (purchases) that might have taken place at various prices along the way.. and then what quantity of BTC did I choose to buy on the various dates.
There could be reasons that any of us might consider our BTC holdings in terms of a narrow number of purchases as compared with assessing our overall BTC portfolio costs and how many BTC that we have right now and what might be the value of the total of our BTC holdings in light of goals that we might have in regards to when we might consider starting to sell some of it.. or creating a plan in which we might sell certain amounts of our holdings based on current BTC prices (presumably selling on the way up rather than selling on the way down) or if we might choose to sell certain amounts of BTC based on time considerations.. so for example if we were to decide to start to sell 4% of our BTC holdings every year, then maybe we might consider that each quarter we might have a goal to sell 1% of our BTC holdings... yet we might not want to begin such selling of our BTC until we have first determined that we have enough BTC or more than enough BTC, and I doubt that our determination of whether we have enough or more than enough BTC would be based on merely our buying of certain slivers of our BTC stash on certain dates at various historical points.
To accumulate BTC you have to start from somewhere and then with passage of time one can derive his own strategy of how to accumulate specific number of BTC. If you have enough cash then one can go aggressive on accumulating Bitcoin but those who don't have enough cash and can't go aggressive can accumulate Bitcoins on dips. The only limitation with buying on dips is that we don't when it's the start of the dip and when it's the bottom. There might be cases when we buying assuming that this is the bottom but price keep on falling. There are ways to mitigate this risk like not to buy at one price rather buy in chunks.
I disagree with you, waiting for a dip in other to invest is not a good idea, when waiting for the dip what if it didn't happen that means you have wasted the time you would have accumulated little using DCA strategy.
Those that are involve in DCA strategy always accumulate more than those always waiting for a dip before they can invest.
Why wait for a dip before you can invest, why not accumulate little by little weekly or monthly.
Bitcoin will not remain at this same price in 10 to 20 years to come so if you start accumulating now you will benefit.
Those who always wait for a dip to happen before they can buy are traders and not long term investor.