I will not diversify my bitcoin into another kind of business by selling it after 10 years, because like you said, for your bitcoin investment to reach 10 years timline, it means that you have been able to accumulate a significant amount of bitcoin, which you should just relax and continue buying with any strategy that you feel is comfortable for you. This is because that is when the compounding profit have a high capacity of generating higher profits for you than before. If you sell some parts and diversify into another new business.
You will miss that compounding profit that would have been accumulating continuously overtime, which might help you reach your your fuck you status faster compared to when you sell part of it to diversify into another business. Another thing is that how are you sure that business will be able to give you profit within a short period of time that you started it. The business needs to monitored and during the early stage, it can take more money and more of your time to grow the business, and due to some inflationary problems a d government policies, the business might fail.
I think you really didn't get his point, he's advising against selling off your investments totally after the supposed 10 years and proposing means to remain an investor. From my understanding, he's advising for worst case scenarios, maybe you're out of funds and want to sell off to maintain your living and his advise is simple. Instead of selling off, you should just take some part of your gains and invest it wisely so that his investments can continue taking care of him while he maintains his investments in bitcoin and works on increasing his portfolio continually while solving his problems with his diversified investments. This is better instead of preying on your investment to satisfy your needs after 10 years.
Lastly, the profit that you will make from your new business is four years with stress and hard work might not be upto half of the profit that your bitcoin investment, that you continue holding without selling a dime after ten years will give you after an additional of four years. Currently, I think Bitcoin investment should be one of the best, if not be best to give you a better profit than any other investment. So these are what we consider before thinking of diversifying. I am not saying that to diversify into another investment that is not on the same line with bitcoin is bad.
I think you didn't do your researches very well before saying this. I do a little agriculture in my country. I plant potatoes and cassava. Potatoes is harvested within 4 months and some cassava stems are harvested within 3 months, 6 months or 8 months depending on what you got. When done well, I get 150% ROI at least quarterly. I'm sure of diversification in agriculture because I currently practice it. So there are businesses that are very profitable and are worth using as means of diversification for problem solving and emergency response purposes while still holding profitably.