If an investor cannot keep an emergency fund or a reserve fund (backup fund), then he will put his investment at risk. Because an emergency fund is kept for danger. If an investor gets into danger while running his investment and there is no one to help him. Then if he has to sell the investment to get rid of that danger, then he will have no end of regrets. You can face many obstacles and dangers while investing. Therefore, an emergency fund or a reserve fund is necessary to deal with any emergency situation.
Danger never comes in a hurry. If you keep an emergency fund, it means that you are going to invest risk-free. Those who do not keep an emergency fund or a reserve fund often lose their investment after being caught in a storm.
I agree with you that without an emergency fund, our investment in BTC will be in danger because of course there will always be many obstacles that will be faced in this life. However, for beginners who want to invest in BTC, of course, in my opinion, they can also invest in BTC without having an emergency fund, but as long as it is only temporary because rather than not investing in BTC at all and if later there are more funds, we can use the extra funds to be used as emergency funds and it would be better if the emergency fund was added at all times because of course by adding an emergency fund, it will certainly make our investment safer.
So of course, sometimes many investors forget about emergency funds, even though it is a fatal mistake and with an emergency fund plus an emergency fund that is always added at all times, it will make us strong in holding BTC for the long term and of course the most important thing is that we don't panic easily because of course in investing in BTC for the long term, we must be mentally strong because not having an emergency fund will also make the BTC we have sold if we don't have a strong mentality.