Probably not enough computing power. Laptops and especially mobile phones. You can literally round the number down to zero. But it would be a fun gimmick.
It allows you to sell your phone data connection, it can easily be adapted to public wifi instances or even a dedicated 5G terminal that has an onboarding via LN.
100% worth looking at streaming sats to public wifi nodes in a mesh network. Have suggested this as a better alternative to the shitcoin that does something similar.
The amount of computing power you would get from the machines connecting to the network is so small, that it wouldn't be worth it. No one mines Bitcoin using normal PCs anymore because their hashrate is miniscule compared to a single ASIC.
Paying via lightning is the only option that makes sense. However, many (if not most) phone plans already offer unlimited data. Many places, like Starbucks, offer free wifi. I don't see anyone wanting to pay sats for wifi if they can just use their phone or go to a nearby Starbucks or library with free wifi.