Miners mine as long as they are profitable or else stop mining and buying Bitcoin with fiat - if they are rational.

When price drops but they continue mining indicates that they are still profitable but with much lower margins.

If you look at https://www.nicehash.com/profitability-calculator/ - which is a shitty calculator but enough for a rough idea - you can see that even the newest ASICs with world lowest electricity costs should only barely be profitable. Which is interesting.