This has been bugging me lately, I wanted to post something in the far future, c. 2039, and ran into the same problem of WP not handling the dates correctly.
But the issue isn’t just in the queries, it is systemic everywhere WP does any sort of formatting or manipulation of dates/times.
I think the solution is going to take adding a library that handles a range of dates outside the unix epoch limit, then hunt down every single date/time manipulation in the entire WP codebase and update the code to use the new date/time functions.
Update: Found a related ticket Historical Dates (Pre 1901) Unsupported in WordPress
So says the man whose biggest contribution to date has been alphabatizing the list of Templates in the Theme Editor. ??
