They're not happy with the profits if they are going to sell now, that's why. People are always greedy, and there's nothing wrong with that since there's another all time high coming, we just don't know when. Also, there's no need to sell your bitcoin holdings if you don't need it for something, unless it is very important and you need extra money. Other than that, I don't see why people should sell their Bitcoin holdings just because the price pumps.

That's true people have set their target therefore they don't sell their bitcoin until the time comes when they achieve their target. If someone buy bitcoin at 69k$ then definitely he will wait for bitcoin to cross this price once again and the price of 37k$ is very small as compared to 69k$. No one hesitate but its a matter of profit and people buy bitcoin only due to their hope for getting more so when they see dip in price then there will be no point of selling for them as target achieving require huge timing.

This time is not good for selling your bitcoin even the price is higher because we cannot miss the opportunity to reap the benefit from bitcoin investment during halving. Those who sell their bitcoin now will either need their money urgently or will be unaware of coming Bull run otherwise this is a big mistake to sell bitcoin now.

The simply understand the value of Bitcoin, mind you it depends on what is going on with the holders, some people won't be able to hold for too long because everyone has their problems, it won't hurt to take profits when the price is surging, people need to survive for sure and those who have held for long term are in good shape, something good is already going on for them I believe, I mean you can't be facing hunger and holding something valuable somewhere, you aren't doing it wrong if you take some part of your profits.

I am still surprised that the Binance drama failed to dump the market, not even a slight move to the down side, that's crazy and also bullish, but I am not too confidence that the pain is over, because I don't trust anyone craving for absolute power, and this is what those companies wanting the ETFs approval are after, things will change so much for crypto in the future, the opportunities won't be that much anymore compare to today.

Investors who didn't sell their Bitcoins are not only they believed in Bitcoin but also they are the ones who can't sell because they bought at $60k price in 2021. I was shocked when I see that 70% of Bitcoin supply were not moved. Possibly, when the price create new ATH there will be a massive dump of price. I believe that lot of them can't wait to sell their Bitcoin.

I believe people are aware that there will be terrible news that will force them to sell their Bitcoins, but since they believe in ETFs and the approaching halving that will help the price to rise, they will not sell.

This data from Glassnode only shows the time span of holdings of these BTC, which ranges from 1 year to 5 years. But it was not said, or you might not have noted, that the data is only about holdings. What about those wallets that are forsaken by their owners, and some of them remain untouched because maybe their owners don't have access to the funds anymore? These two reasons would be considered valid for the answer of why they are not selling and when they are planning to book the profits.

Because in 2021, when BTC was making its all-time high of 69,000 dollars, many people did not book, which might be because they had no access to their funds, or some might be thinking that BTC could touch $100k, or they could have any other target in their minds to achieve, and in order to get them, they did not book profit and exited the market, and then the market came down and they got stuck in it.

In my opinion, this is not a good approach because if you are planning to sell a thing where there will be fewer buyers to buy it due to its expensiveness, then you might face problems getting a legit buyer.

Hold tight, one of the main reasons why bitcoin raising continues. Assume most of the holders are holding Bitcoin for upcoming ETF news. They want to take advantage of the upcoming volatility for ETF approval. On the other hand, Bitcoin halving is quite near, and a massive pump is expected in this situation. Holders don't want to miss the train when Bitcoin starts bullish. Though I am expecting to buy in the $30K zone, I am not sure if it will reach those points.

There are some people who doesn't have lots of BTC or you can say they only have decent amount or small amount compared to those who have lots of Bitcoin. Reason that I can think of why some people doesn't want to sell or use their Bitcoin is because of transaction fees getting higher and other reason is they are looking for much higher price before they can sell for profit or use to buy something because I would also done the same.

It's because that we're about to see the halving in the next few months next year and that's why many are hesitating to sell their Bitcoins.
The effect of it is going to be greater and the price is believed to be higher than that when we're done with it. The cycle and the thought of what can happen next afterwards is what making most of us to hold a little bit longer and we're not willing to sell at any point, at least selling in bulk.

 You know that's individual's choice especially if the bitcoin hodler is up for something bigger and more profitable. Smart bitcoin investors do not compromise their profits if they decide to sell, but when they do, they make sure that those profits will be utilized well even if the highly desired profits fail to achieved.  Most probably, bitcoin holders unable to decide well when it comes to selling because they know already the potentials of bitcoin, that its more ideal when left hodling as it attract more profitability in the making.

By unused, I believe you mean dormant, and that is how we refer to wallets that haven’t transacted in a long time. Do not forget that the owners of the wallets may not necessarily be intentionally waiting for let’s say when Bitcoin is $100k. They could have lost their private keys/mnemonic phrase and hence, the stagnation of the wallet.