Respecting -E and -I isn't a problem per se - the problem is moving the _Py_CoerceLegacyLocale call to a point that's incredibly late in the startup process *just* to get it to respect those flags.

I don't actually mind if you reinstate the extra pass through the command line arguments just to check for -E and -I early enough for it to affect a properly located call to _Py_CoerceLegacyLocale, I just don't think it's necessary to do so.