"They buy up struggling companies with the aim to revitalise them, or otherwise recoup the cost of investment+ profit."

1) Nope, they are focused on taking advantage of customer lock-in to raise prices, while reducing operating expenses to increase cash flows. There may be some initial reinvestment to increase surplus of its users, before raising prices substantially. 2) "recoup the cost of investment+ profit"? Yeah lets see if that pans out. The acquisition price is assumed to be under a going-concern basis in perpetuity, if they muck things up with the choices they make the acquisitions have a limited life to increase and capture those cash flows to deliver a positive NPV investment. The demand for the firms products are not perfectly inelastic w.r.t to price.