There's definitely a few billion a year in revenue for Starlink if they sell very low latency, medium bandwidth connections between Asia, the US, Europe and Australia to trading firms. Even if the reliability is much worse than fiber.
The routing paths traveling via ground stations, you mean? My understanding is that they were experimenting with improvements to this, they just haven't deployed anything yet.
A radio will beat starlink on ping times. Even a simple ham bouncing a off the ionosphere can win out over an orbiting satellite, at least for the very small amounts of data needed for a trade order. The difficulty in such schemes is reliability, which can be hit-or-miss depending on a hundred factors.
