If you think that’s bad, look at what “1” means.
(And, honestly, at least windows’ “last big calendar change” and excel’s “start of the century when we wrote it” are reasonable points. The unix “let’s make it recent so we can fit an absurdly small unit as an integer!” Epoch is just… Weird.)
1: what the frick are you doing in Excel that needs even 10^2 columns? Rows go up to 2^20 (~10^6), and the thing starts to run like ass way before that.
2: Excel does have a RXCX format, if you really do need to go out hundreds of columns.)
3: feel free to ignore. Bitching about being forced to use the wrong tool is definitely more stress than anyone needs.