I agree, it would be bad for the whole industry, but I also don't see WBD wanting to sell the whole company, just pieces here and there if they are looking at selling at all. WBD literally just became a thing so I doubt they WANT to sell yet, aside from maybe their animation houses.
Let's also take into account that Zaslav has said the crown jewel of WBD is DC, so I actually have a very hard time seeing him turning around and selling DC so quickly. Maybe downsizing the company, spinning off CNN, Cartoon Network, shuttering TBS, etc.
I don't think any deal, if one happens, would be nearly as big as you guys have in your imaginations and I don't think DC would be a part of the deal either.