The entire entertainment sector is readjusting after AT&T got legal clearance to buy Time Warner and Comcast topped Disney's bid for a key portion of Twenty-First Century Fox's assets, CNBC's Jim Cramer said Thursday.

"The industry finally got a two-part catalyst: a federal judge who wants old media to have the firepower to compete with new media, ... and Comcast, parent company of this network, has come up with a high bid for Fox that says everything else in the group, literally everything, may just be too cheap for buyers to ignore," the "Mad Money" host said.

While he didn't necessarily agree that companies like Amazon and Netflix — the "new media" — were spelling doom for more traditional players just yet, Cramer could see why Comcast announced almost immediately after the AT&T ruling.

By announcing its $65 billion bid so soon after the verdict, Comcast sent a signal to investors that what matters now in the Fox bidding war is money, Cramer said.

"With such a clear ruling, one that could make the Justice Department look foolish if it tries to stop anyone from buying these Fox assets, a Comcast bid, well it's the same as a Disney bid — they're equivalent," he explained.

"So all that matters is price, and Comcast's price seemed to be just high enough to make it hard for Disney to compete, but not so high that it crushed Comcast's stock," Cramer continued.

And based on Thursday's action in both Comcast and Disney's stocks — Comcast up nearly 5 percent and Disney up 2.3 percent — the "Mad Money" host wondered if investors were seeing the companies with fresh eyes.

"No matter who wins this bidding war, the market is ... screaming that the stocks of both Disney and Comcast are substantially undervalued and they both deserve to go higher," Cramer said.

After all, even without Fox, Disney's business has benefited from tailwinds in its movie business and is working hard to make its over-the-top online ESPN offering attractive, Cramer argued.

And Comcast, which is likely willing to pay more than Disney for Fox's assets, has steady cash flows and sprawling cable and entertainment franchises that would neatly "dovetail" with Fox, he said.

"Here's the bottom line: yes, I want the rally to be more broad-based. But when you get this kind of revaluation of an entire sector, it's a real positive. A stock like Disney, which should've really been going down if it's planning to increase the amount of stock it's offering for the Fox assets by a dramatic amount, actually managed to rally and that is incredibly telling," Cramer concluded. "In a market that's gotten more difficult with tariffs and rate hikes galore, this revaluation of all media values ... is definitely something worth cheering about."