Starlink isn't a replacement for Comcast if you care about latency, but it is for rural dialup and satellite Internet. And probably a whole host of new usages, such as sensors deployed to the field, etc.
edit: Okay, so folks don't like my fairly honest take on Starlink? It's a great service that's going to make a ton of money. But it doesn't replace all classes of Internet use. That's unrealistic.
It actually might be better than cable in many situations. Cable upload can be terrible, and where I live, cable actually goes down when it rains which makes it no more weather resistant than a satellite Internet solution like Starlink would be.
There is that whole thing about highly dense regions not having as much Starlink bandwidth per capita, tho.
I've been to plenty of small rural towns where cable TV and internet existed, was better than DSL, but worse than what Starlink will be offering. Their population density is low enough that Starlink could provide service to most if not all the residents.
(Bandwidth of an individual satellite) x (the number of satellites they will have when they get the full constellation up) puts a cap on how many customers Starlink can handle and still deliver the specified performance. That cap is way lower than the number of Comcast subscribers.
I think that depends on how oversubscribed Comcast is. My local cable co only allows 1TB/month of data because of how oversubscribed they are. Even with that limit, speeds still drops a ton during peak use.
I'm getting about 100 million subscribers with the current fleet (1700 satellites) if they oversubscribe and limit subscribers to 1tb/month like my local cable co.
edit: Okay, so folks don't like my fairly honest take on Starlink? It's a great service that's going to make a ton of money. But it doesn't replace all classes of Internet use. That's unrealistic.