Historically, Google had a give-and-take with SEO. You can't make SEO companies go away, but you can curb the worst behavior. Google used to punish bad behavior with a poor listing, and you had to do some work to get it back into compliance and tell Google it's fixed up.
It wasn't ideal, but it functioned well enough.
The drive to make search more profitable over the past few years seems to have meant dropping this. SEO companies can get away with whatever. If they now have the whole manual, game over. Google of a decade ago might have done something about it. Google of today won't bother.