Can you buy impact?

Yes you can. Only recently I came across an incredible example how a university has been pushing the own “impact”. It is the astonishing story of the King Abdulaziz University ( detected by Bits of DNA ) and goes back to an earlier Science article

In 2011 Yudhijit Bhattacharjee published an article in Science titled “Saudi Universities Offer Cash in Exchange for Academic Prestige” that describes how KAU is targeting highly cited professors for adjunct faculty positions.

Looks like the professional football league. If you do have a lot of money you can pay for whatever player you need for your club. There is, however, a big difference: As a player you have to show up on tht football field, as a scientist you just have to drop your name somewhere.