You mentioned it yourself; they are "long-term investors," by virtue, they are not short-term or medium-term investors, so why the panic? They ought to know what they were signing for. For me, they should continue to hold their Bitcoin. As history would have it, what's happening now is not an isolated case, and Bitcoin always get back higher over time. Patience is advised!

You ask about long term investors, then the answer is very simple "HODL".

A real long term investor does not care about short term fluctuations, they only see the real potential of Bitcoin as based on its historical price we can conclude that overall it's growing, so they should focus on that direction and ignore those short term fluctuations, and if the price dips, it's even a good time to accumulate more.. that's being very positive.

They should stay away from FOMO and trust in long-term investments.

When does FOMO occur? When you do not trust Bitcoin or do not know about its nature. Bitcoin has always been volatile and there are deep periods in every cycle. So there is no need to panic if you see a decline.

You are talking about long-term investors, if they behave like that, they may not have to face losses. But if they behave like traders or short-term investors, they will definitely face losses. Avoid changing goals in the middle of the journey.

Since you are talking about the long term, just focus on HODL and try to take advantage of the opportunity to buy at a low price.

Now if your Bitcoin is not lost or hacked, then you will not lose everything just because of the price fluctuation, you just have to be patient and HODL. Look at the past history, the price of Bitcoin has fallen a lot in the past but has recovered again.

I do not see any signs that the market is headed for a deep correction; despite the Binance hack and all the negative news surrounding the security of services and hardware wallets, the price has neither collapsed nor undergone a sharp correction.
The sale might be driven by security-related reasons, rather than investment motives or a fear of a price collapse.

Those who call themselves investors are those who build themselves not by wealth but with a long-term mindset. They don't sell just because of the price correction. Instead, they will buy more. They prefer to hold and collect rather than be afraid.

For them, losing happens when you are panicking. That is why they don't use their emotions. Instead, they remain patient and disciplined. But this can only be achieved if you also have the mindset of an investor.

The fluctuations of Bitcoin's price are nothing new, and as a beginner investor, you just have to get used to it. Volatility is always constant, and if you are disturbed by it, you can never hodl Bitcoin.

The reason why investors panic due to the fluctuations of Bitcoin's price is that they do not understand the volatility of Bitcoin, and they may not be holding for the long term; it is possible they have a specific time frame in which they want to make a profit from Bitcoin. If you understand Bitcoin's volatility and make up your mind to hodl for the long term, I don't see why one should be bothered about the volatility of Bitcoin.

First they have to understand that when There’s decrease in market prices , it doesn’t affect their bitcoin holdings only affect the value of their bitcoin stashes . As long as an individual continues holding, regardless of how much the price drops, they haven’t actually realised a loss unless they eventually sell at a lower price. The other way they can lose all their assets is through poor management which can lead to scammers getting access to their assets .

So as a long term investor, is quite easier to handle dip compare to short term investors . Because your focus already is on longterm so you’re aware that the market usually under goes correction before prices rally or push further to any direction the market heading to (uptrend or downtrend).  So your focus for now especially as a low coiner or a no coiner , is accumulating as much as you can . Knowing are to take advantage of any market conditions.

If any long term holder is scared of Bitcoin price action I am sure that they lied to you that they are long term holders, it's only a newbie that can behave that way.

A genuine long term holder will have understand the market very well, they would have know that all it takes as a bitcoin holder is to just hold, the time will come where all holders will be paid for holding.

It's only beginners that get scared and always look at the present value of your portfolio every hours of the day, a long term holder means someone who is already familiar with the market behaviour.