EM redshifts alone would invalidate that hypothesis. It doesn't matter how fast you travel, EM redshifts follow specific laws that we cannot see breaking at any

EM redshifts alone would invalidate that hypothesis. It doesn't matter how fast you travel, EM redshifts follow specific laws that we cannot see breaking at any point observed in the universe. It is more likely that physical laws have localised variations that we cannot tell from any discernible distance. Maybe pockets of vacuum do shit that we cannot fathom and if we observed it, we'd break the code for reality.