The question, wrote analyst Martin Pyykkonen of Rosenblatt Securities, is "whether the revenue substitution from skinnier bundles and/or a la carte channel plans will at least approximate the traditional cable bundle revenue over time."
Disney's profit-forecast cut suggested otherwise.
Disney CEO Bob Iger told analysts Tuesday that while the company is proactive in supplying ESPN to small online packages like Sling TV, "we don't think right now it's the greatest opportunity."
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Iger said he didn't see "dramatic declines" in pay TV packages like those offered by DirecTV, Comcast and others "over the next, say, five years or so." He said he would contemplate options for ESPN if the traditional pay TV universe continued to shrink, "like going direct to consumers." (Disclosure: Comcast is the parent of NBCUniversal and CNBC.)
In the meantime, it was unclear whether individual channels and skinny channel bundles were succeeding.
Time Warner said its HBO Now app was the top-grossing app in Apple's iTunes store in May and June following its debut in April, and it was investing more in programming.
HBO chief Richard Plepler tried to allay fears that the single channel offering was causing people to drop bigger TV packages.
"We have seen less than 1 percent of HBO subs leave the bundle to go get HBO Now, which is exactly what we suspected was going to happen," he said. "We feel very good about it and we think HBO Now will be very profitable in the coming quarters."
The comments didn't generate overwhelming enthusiasm on Wall Street.
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"The take rate is encouraging but I think it's still early," said Vasily Karasyov, senior research analyst with CLSA Americas. "You have to see conversion from free trial to full pay subscription and so on."
Meanwhile, CBS CEO Les Moonves was upbeat about CBS's go-it-alone online channels called CBS All-Access, which provides CBS content for $6 a month, and Showtime, with original shows and movies for $11 a month.
Not only are its online audiences younger—and therefore more valuable—but it is getting paid more for each subscriber than through traditional distributors, making any shift a benefit.
"Each of these deals resets the value of our content higher than it was before," he said.