When the SEC filing is made, we'll get to see how the deal is structured. The $20 billion from TD Securities becomes a debt obligation of the combined company. There's a tax break in equity to debt conversion, and a second tax break for carried interest. [2] There may be a preferred stock deal or debt refinancing so that TD gets their $20 billion back. Usually, the private equity firm exits within a few years.
[1] https://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.23.1.121
[2] https://www.pgpf.org/article/what-is-the-carried-interest-lo...
A third of the deal is financed with debt. A fifth is financed with cash. The bulk—fifty percent—is being financed with equity. An LBO would see debt and a thin tranche of cash finance the bulk of the acquisition.
The one I was most familiar with was the Discovery “acquisition” of Warner Brothers. Though apparently that’s a little complicated because AT&T was divesting itself of Warner.