Those “very short programs” are useful even if the universe has no bias towards them.
They are? How? If they have no privileged status and phenomena are due to long programs as likely as short programs (leaving aside the issue of how they works given that there are so many more long programs than short ones), then they don’t predict well. That doesn’t sound useful.
It’s just Occam’s razor.
And what justifies Occam’s razor if the universe has no bias towards short programs?
They are? How? If they have no privileged status and phenomena are due to long programs as likely as short programs (leaving aside the issue of how they works given that there are so many more long programs than short ones), then they don’t predict well. That doesn’t sound useful.
And what justifies Occam’s razor if the universe has no bias towards short programs?