non-sequitur - mining is still a game of odds.  If both a and b get a solution in exactly t time, then yes, t_delay matters, as whoever has a lower t_delay stands a much larger chance of winning out.  But if a finds a solution in 5 minutes while b takes 8 minutes, t_delay can be up to 3 minutes before it matters.  Yes, the trend over the long term is important as those with a lower t_delay will win out on average - see also HF traders - but this is a problem in search of a short term solution while planning for a long term one.  And in that, a high latency internet is still preferable over no internet.

Sure, the signal can only go from Earth to orbit and back so fast - but that doesn't mean there aren't different providers with different contract levels giving different latency.  I was referring to that difference, not the difference with direct lines or The Postman.

I'll leave it to Bitmain to answer if they've considered that option - though I suspect that if you can get a modem going (and I can only presume you're thinking 28k8-era 'modem'), you've already got the base infrastructure for much better connectivity.  Whether it's worth throwing money at getting the endpoints to go along with that, instead of throwing money at replacing the fiber and using satellite in the interim, would be a follow-up question.