Market sentiment is changing and Bitcoin is always associated with volatility, so it is difficult to say in this process that only holding it for the long term will yield profits or maybe it's not even possible to say depending on how much Bitcoin you've accumulated and how long you've held it. Holding for the long term is definitely a broad-mindedness for investing but if you have enough Bitcoin and are aware of the market situation there may be a chance to make a profit, because of the rapid rise and fall of the market even if you have a portfolio full of Bitcoin no distinguished investor can guarantee a profit.
Try not to be confused about Bitcoin, you are a senior member, I expected you to know better that the way Bitcoin is wired, it is more beneficial to hold a little bit longer because since Bitcoin is an asset that appreciate in value overtime even common sense will make us understand that as time passes by, it value is going to increase and you that is holding it, is going to make more money.
There is no guarantee on this, although bitcoin is the best digital investment if not the best investment presently, but we must remember that we are not guaranteed any profits in bitcoin. We are only having a fair bet on bitcoin by choosing to believe in it, accumulate and hold for a longer term, which is Ideal for bitcoin investment, yet it doesn't change the fact that we are not guaranteed profits which IMO is what the guy you quoted is trying to imply.
If an investor invests in Bitcoin for short-term profit, there is no chance of guaranteeing profit, even long-term investment cannot guarantee profit, but the possibility of long-term investment is much higher than short-term investment. Those who hold their investment and if they continue to collect Bitcoin regularly, it is possible to easily increase the amount of Bitcoin. Everyone who has held Bitcoin since its discovery has benefited. No one has lost yet if they are able to hold it until the highest price. I will not say that those who bought from the highest price have also suffered due to the price decrease or price correction because as long as they have Bitcoin, they are not affected. They will be able to determine the profit and loss at the time they sell. If the previous position of Bitcoin and the future possibilities are considered, those who buy Bitcoin even at the highest price will also be able to benefit in the long term.