Stephen Colebourne wrote:
An uninhabited location would effectively be on LMT
That's not been the usual practice with the tz database. LMT has been a standin for "there were clocks here, and they were on local mean time or solar time or something like that, and users who care about the details are barking up the wrong tree". It's not just the LMT offsets; even the transition times from LMT to standard time are mostly standins that should not be taken seriously, for reasons already discussed. And even if we were to change the tz database to agree with this new interpretation, the old McMurdo data would still be incorrect, because it did not say that McMurdo was on LMT while uninhabited. More generally, the tz database isn't designed to answer questions about which parts of the Earth were inhabited when, and it's implausible that actual users would use it that way, not merely because it's an odd question for them to ask, but also because they'd get typically get the wrong answer regardless of which version of the tz data they used.