It's not only dangerous because PayPal itself is so lenient on chargebacks from within their own interface, but the very fact that I can initiate a charge back from my banking interface is an extra risk that makes PayPal even less desirable as option to use. It doesn't matter whether you use the G&S or F&F option, when you initiate a chargeback PayPal will screw you hard.
I know someone who lost considerable value thinking that it's safe to accept F&F payments. It wasn't related to crypto, but the buyer aka scammer managed to get the product and a refund, leaving the seller out of a lot of money. PayPal = making scamming easy and profitable. People who knows this but still continue to use PayPal have no right to complain when the odds stack up against them.