Why should I use a paper wallet when I can buy a $60 hardware wallet and store my coins there?
This is much more convenient if you want to store multiple coins, or want to do so in the future. Previously, there were no hardware wallets or they were expensive and untested.
It is by choice and what you think is best for what you want.
Paper wallet cost nothing to setup and you can set it up within few minutes, yet it is secure. Although, having a hardware wallet is good for altcoins.
Having hardware wallet is useful for multiple coins, but for bitcoin, you can still use a paper wallet because of some reasons, like not spending your coins over long term.
Paper wallet has gone beyond using bitaddress to generate a single address wallet, you can even use iancoleman or a reputed wallet like Electrum on an airgapped device to generate a paper wallet, which means to back up the seed phrase on paper or somewhere safe like on metallic sheet, having some private keys and addresses backup that you can later run on online wallet whenever you want to spend your bitcoin, making easy means of making transaction possible. But the main purpose of a paper wallet is for a long term storage.
Some people may prefer papper wallet as it is a cold wallet with no transaction made on it before, unlike hardware wallets that still connect by some means like USB, bluetooth or NFC.