I think it's quite different. It involves money, but QE is all about monetary supply and interest rates alone. Buying entire companies comes with a lot more implications, like decision-making power over the organization. You want that for API keys, but do you want that across the board? Seems like regulation would be much cheaper.
Thanks for replying, today I corrected a misunderstanding i had about QE. I had previously believed they were buying and selling stocks (I misunderstood their usage of "Securities")