Of course, what you are worried about could happen and that is because mining has indeed stopped, and it is difficult not to do that because they need each other.
If the internet is indeed down, then it will not be able to connect and that connection requires an internet network that must be available properly, so if there is none, then it will stop and die along with the internet.
That's right, that no one will be able to add anything to all their activities, so no transactions can happen.
We don't need to discuss topics like these, because we all know that if miners don't work, the blockchain will be disrupted, and the network will become meaningless. I also can't foresee what could create such a scenario, even if farms are destroyed, somewhere in the world, many individuals are still continuously generating blocks to be ready to serve everyone.
Suppose the blockchain is delayed due to a power outage, and crypto also cannot be withdrawn from the blockchain. In that case, we will have many other concerns instead of just focusing on market sentiment or the reaction of top coins. Food, drinking water, and jobs will be what we talk about when the internet is down. Crypto holders will need enough faith to continue holding their keys, wait for the power grid and internet to be restored to continue investing or simply take profits.