But diving into the terms and conditions of the new unlimited mobile plans reveals too many limitations for most home Internet customers to depend solely on wireless, longtime cable industry analyst Craig Moffett says. The plans don’t allow truly unlimited usage, with reduced download speeds imposed in congested areas after 22 GB to 30 GB of usage per month. And carriers have added even lower data slowdown triggers for use of the wireless connections to get a laptop online via tethering.

“Wired broadband losses to wireless substitutes are likely to be modest, primarily nibbling at the edges with lower income and lower usage customers most at risk,” Moffett says in a report on Wednesday.

Given the limitations, on an economic basis, dropping a wired Internet connection would only make sense for about one out of four people—those with the lowest data usage at home, the analyst calculated. And even among that group, a majority would not save money since they would likely have to pay more for wireless service to upgrade to an unlimited plan.

Even before the new unlimited wireless plans arrived on the scene, some data points about growth of home Internet cord cutting have emerged. The percentage of adults relying only a smartphone for getting online rose to 13% in 2015 from 8% in 2013, while only 67% of adults had home broadband connections, down from 70% in 2013, according to surveys by Pew Research. But the percentage of households relying solely on mobile Internet connections as measured by U.S. Census Bureau surveys ticked up only to 6% in 2015 from 5% in 2013.

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Still, the growth of wired Internet connections sold by cable and telecommunications providers has been slowing. In the fourth quarter, the industry increased total broadband subscribers 3.3% to 101.2 million, Moffett notes, down from a growth rate of 3.9% in the same quarter of 2015 and 4% in 2014.

And that could create a perception that the lucrative home broadband businesses at companies like Comcast (CMCSA), Centurylink (CTL), Charter Communications (CHTR), and Verizon (VZ) are at risk from the unlimited wireless plans. Stocks of some entertainment companies took a huge hit two years on just some early warning signs that cable TV cord cutting was growing.

“Further deceleration poses a risk no so much to numbers–at current penetration levels, it is only reasonable to forecast that growth rates will slow–but perhaps more to narratives,” Moffett writes. “That is to say, the story that we may be seeing the front edge of wireless substitution is likely a larger risk than the reality.”