I don't think it's just all about the value; if you are living in the country with a very cheap electricity rate or free, even with the price drop, you are still making some profit while you cover the electricity cost.
It's a bad idea to go into this business and build a small mining farm without first calculating everything because you might end up selling your units and coins at a loss.
You should calculate your units' hash rate and electricity cost if you can sustain it until the block halving because if you are mining for many years, the maintenance cost plus electricity could wreck your pocket.
Do you think miners will mine simply because they see so many people mining BTC?
You need to consider calculating everything except for those people who mine solo because they don't care about the electricity cost, and the units they use are small units like BitAxe, which is not power-hungry unlike new Bitmain units nowadays.
If I were you if your nephew is planning to enter into this business, I suggest helping him first to calculate everything using this tool below. If you are living with very cheap electricity costs or have a free power source, then the profitability is high even if BTC is bearish.
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https://whattomine.com/asics-
https://www.mycryptobuddy.com/bitcoinminingcalculator