This is not a good idea to take loans from banks just for crypto use because you know better that crypto is volatile and here you will face difficulties to achieve your goals which also have no guarantee that you will earn with this loan amount.
If you lose in crypto then you will want to recover that money back and also will wish to repay your borrowed money to the bank but unfortunately you will be unable to do any of these tasks.
Agree. It is better to use safe funds for crypto investment. It is not recommended to use loan money from banks for crypto investment. Crypto prices are very volatile and unstable, we can't expect to take profits any time we want. If we invest carelessly, we may end up with losses and may be trapped in the loan. This should never happen in crypto investment, the loan money must never be used for crypto investment.
Ideally, as you said and of course, everyone really agrees if you have funds available to invest in, but not everyone has more funds to be able to invest in crypto. One solution is to borrow from a bank, assuming we are able to pay the installments due. This loan, I think, is something that is legitimate and very good.
Analyzing like now where prices are certain to increase, there is no harm in doing so. All investments are also the same, it is certain that there are also those who borrow from the bank but adjust it to your own situation in terms of returns.