Yes, you are missing something.
Any DEADCODE that can be added to a 1kb program can also be added to a 2kb program. The net effect is a wash, and you will end up with a 21000 ratio over priors
Why aren’t there 2^{1000} less programs with such dead code and a total length below 10^{90} for p_2, compared to p_1?
There are, but what does having a length below 10^90 have to do with the solomonoff prior? There’s no upper bound on the length of programs.
Yes, you are missing something.
Any DEADCODE that can be added to a 1kb program can also be added to a 2kb program. The net effect is a wash, and you will end up with a 21000 ratio over priors
Why aren’t there 2^{1000} less programs with such dead code and a total length below 10^{90} for p_2, compared to p_1?
There are, but what does having a length below 10^90 have to do with the solomonoff prior? There’s no upper bound on the length of programs.