Anyways, an example of what I would use stablecoins for: I expect the price of $TOKEN to go down so I swap it for USDC. While I'm waiting for $TOKEN price to go down I lend my USDC on Aave for ~3% APY (and yes, there is smart contract risk here but I chose Aave in my example for that reason). When $TOKEN price drops enough I swap the USDC back for $TOKEN.
Another situation: I want to send my family member money to help with down payment on a house. I don't want to sell $TOKEN because I think the price will go up, so instead I lend $TOKEN on Aave and borrow stablecoins. I send stablecoins to family member (worth noting this would be difficult to do in FIAT due to the amount) and when he pays me back I can then withdraw my $TOKEN.
One more: I just sold a jpeg and want to make sure I have enough cash to pay taxes next year. Instead of hoping my $TOKEN price will stay same or go up I sell some for USDC to cover taxes