I don't think anyone is manipulating anything ... it is just more people with higher scores are entering draws and that is because people now are getting more informed about Express Entry. I myself was very skeptical about it and always thought of it as a scam until my friend convinced me to enter and basically forced me to, and now I see that it is legit.
Personally I think there is hope for cut off score to drop lower than 460, especially if a draw happened this week, but I would have to agree that we will see the score holding up more often in the 460s.
Going forward, scores would become more competitive as more and more candidates pour in with higher numbers, you are right but we might see a dip every now and then based on the draw size and consistency.
In 2016, scores used to be 480s and 490s even when the invitations numbered 2500s. That is because at that time, there was a similar competition and scores used to dip to 470s every now and then based on b2b draws.