The article treats these problems like they're new and dangerous but embarrassing people with their likeness and reproducing other's work has been around for millennia.
As the article mentioned these videos can not pass as genuine; they're obviously fakes. Rather than trying to pass off a lie, this is more akin to fiction where you're required to suspend your disbelief. At least until the technology improves.
What would be the ethical implications of using deepfake tech to anonymize porn. IE, alter face and possibly tattoos and voices such that the person was not recognizable by friends/family?
They do it for a bunch of reasons, more to distinguish from I guess the competition. Things such as outright impossible body geometries (from tentacles, various types of combined male/female bodies, robots, cyborg, ...) to otherwise difficult/impossible sex acts (e.g. a kinda cool one was jumping out of a plane, then having sex before crashing into the decor) or things impossible with humans (like sex with various types of (partial) android-type robots where we're not even remotely close to having advanced enough control algorithms to do that).
This certainly looks like it has the potential to be more popular than porn. Perhaps exploitation will mean humans will always be cheaper, but I don't think so.