[bluesteel44]

Banks can position themselves to benefit from a depreciation of any given currency, miners are tied to the success of the one they've chosen.

[SomeStupidPoint]

Can a miner not distribute their effort and holdings?

[Obi_Juan_Kenobi]

Miner hardware is tied to the specific proof-of-work algorithm used in the cryptocurrency they mine. They make extensive capital investments that are, at least in the case of Bitcoin, useless for any other purpose.