Maybe selling an investment is a personal decision for everyone but I wouldn't consider the decision to sell as reasonable if there aren't enough Bitcoins. Moreover this post of yours may serve as an example for investors, this post makes it clear that an emergency fund is very important for every investor. If you had an emergency fund in place before investing, you would never have had to sell Bitcoin and instead would have had the opportunity to buy a little more Bitcoin during a market dump. We should not invest all our money in Bitcoin, it may have more risk potential. So I think instead of selling Bitcoin now, buy more.
Bitcoin investment is for the future, it can serve as a hedge to emergency situation in the future if one have accumulated enough Bitcoin, the person that sold his Bitcoin for Eid shopping would only regret if he sold a large portion of his bitcoin for it or his portfolio is not up to 4 years and more. Asides that, it's a personal decision like you said, anyways my opinion is that even though someone has a large portfolio and has invested for a long time it would be best to diversify some portions into a business or something that would generate more income for emergency situations and to continue building the portfolio, if he keeps withdrawing from his portfolio and not add into occasionally, maybe because he feels he has enough, at some point the person would regret it when they've taken out about 70 to 80% of their holdings. That's why the DCA is highly recommended and it's very compulsory to have a steady flow of income to keep one's Bitcoin investment going for as long as possible and not affect even when some portions is withdrawn from it.