Hey are absolutely not replacing “legacy” isps and certainly not mobile. Even if they had perfect coverage, sat signals are way too sensitive to obstructions.
And come on 100/10 is not bad despite the other 10gig fiber
On the other hand : "Starlink users typically experience download speeds between 45 and 280 Mbps, with a majority of users experiencing speeds over 100 Mbps. Upload speeds are typically between 10 and 30 Mbps."
That doesn't sound meaningfully different. What is the price difference ?
What I'm saying, is as soon as there is a real competitor pressure, ISPs can upgrade their deployments in under a year or two, even without touching buried copper. Of course they can also choose not to do that too :) .
(and it's an area where it would need orders of magnitude improvements to address the density of cities, it's not really close at the moment)
In the past I've worked on consensus based protocols like the ones used in modern cellular systems; basically edge devices register with a controller system that then coordinates time slots for distribution/use of bandwidth for the limited spectrum. Adds a lot of complexity and requires highly accurate time synchronization mechanisms to have any hope of working, but they certainly could leverage something like that to further increase support at higher densities. That is, if they're not doing that already.
To decrease that latency in high density areas like cities they'd need to reach for something like terrestrial microwave relays to add more connection points from adjacent (in horizon) "freer skies"
Maybe some decent revenue offering sat to cell for the traditional carriers.
For the microseconds-chasers, there's microwave relay links, say between Chicago and New York (ref e.g. https://bullseye.ac/blog/economics/inside-the-world-of-high-...). Sending a signal up a few hundred km and down again a few hundred km adds way too much latency, and signal-hopping between fast-moving satellites adds way too much jitter for "such applications".
A normal person will probably never notice the difference between 4g and 5g because of what they use their phone for, and giving every household a proper fiberoptic line is probably a much better quality of life improvement. But ISPs dont want that future. They want everyone to be connected to these neighborhood hubs that don't require last-100m-cables and expensive construction. The same can probably be said for Starlink. It's "Good enough", and that's good enough to get sales. They don't care about the quality of the product they deliver, or if fiberoptics are superior. They care about sales.