implementing long term archive encryption
The AES solution will fail if either:


the secret key is leaked, or
AES-256 is broken.


The RSA+AES solution will fail if either of the above happens, or if:


RSA-4096 is broken.


Thus, even without considering the relative likelihoods of these events occurring within the next 30 years, it is clear that the AES-only solution cannot be any less secure than the RSA+AES one.

Of course, the RSA+AES solution has the practical advantage that the system performing the bulk of the work (AES encryption of data) need not know your secret RSA key (although they will, of course, still need access to the AES key used to actually encrypt the data, not to mention the data itself).  You will need to decide for yourself whether this extra feature outweighs the risk of complicating your system by introducing an extra point of potential failure.