Perhaps it will not be as efficient , however we cannot control the power consumption of the transit on wired or satellite, satellite by its design is going to be solar though. I don’t think ISPs are look at carbon footprint for their equipment at the moment
I am side stepping the entire argument on cable laying v sat launch for setting up the infra . Likely satellites are have lesser carbon footprint than cable laying, but there are lot of variables .
If we consider carbon CapEx - Falcon 9 is 500,000 kg of fuel. For that amount of fuel you could lay down a trans-atlantic cable. Then conside that sattelites still need to be serviced by large base-stations across the globe linked by optic fiver.
Then consider that a single cable lasts much longer than sattelites do in orbit and carries more data.
Then conder the fact that radio transmission across almost a thousand kiloneters is a lot more power intensive than optical transmission.
Satellite internet is cool, but energy efficiency is not one of it's features.
Most cable laying ships are in 10,000 tonne size , ships this size use typically 50 tones of fuel a day at cruse speeds , cable ships travel much slower than that. The fuels ship typically use is one of the dirtiest as compared to RP-1 kerosene a falcon 9 uses. I am not so sure rockets are not cleaner approach.
On the downside The life of a cable is 20 years or more , as compared to only 5 years of a starlink sat . Definitely lot more data can go through a cable , it is not apples to apples comparison .
I am side stepping the entire argument on cable laying v sat launch for setting up the infra . Likely satellites are have lesser carbon footprint than cable laying, but there are lot of variables .