You know, that's like saying if you're already swimming in shark infested waters in the Pacific and Atlantic Ocean, then there's no added risk to do it in the Indian Ocean.

Or if you bed Lisa, Abby and Mariah unprotected, then there's no added risk to do the same with Jen.

The risk is incremental.

Edit:
Actually, to more accurately make the point, I should have said that if you bed Lisa, Abby and Mariah who has the cooties (Corona) with protection (mask, social distancing, etc), you do actually take on more risk if you then go on to bed Jen who also has the cooties, even if you still use protection.