Believe it or not, btc is not that volatile after 2017
Let's say I purchased a nice luxury watch for 1 btc today and tomorrow it costs 0.3 btc, that would be awesome!!
You're telling me that the bitcoin price went from $20K to $60K and my portfolio has tripled in $ value in 1 day!!
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Here's the reality, most people who treat bitcoin as a long term investment or savings account, have a mental model of volatility
Let's say your life savings is in Tesla and it lost half of its value from the top, it will bother you due to price anchoring, but if you were not planning to sell your Tesla in the next 5 years, why does it matter?
Or if you have half of your net worth in British Pound as your wife is from there and that was something you both agreed upon, now you've lost 30% of value against the US $. No big deal, right, since that's part of the global volatility of values
Same for Bitcoin holders
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I have a bitcoin spending wallet in btc as I have to pay some online service providers like VPS or VPN in btc, but it's only a few thousand $
Since I quit my job almost 2 years ago, what's important is not to exhaust the Bitcoin quantity equivalence. Increase is fine, but not decrease it significantly
US $ is for spending, Bitcoin and crypto assets are for savings or long term investments
Thanks to some luck in good crypto projects, Bitcoin equivalence is increased
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I've seen tweets of Ethereum holders having a similar mental model for example, they'll say something like, I spent 5 Eth in Vegas this weekend
Whatever works for people, but your initial question or scenario is not based on reality. I very much wish it was, though