For old wallets (2009-2017) there is not much to do beside having "performance counter data" which can lead to guessing private keys.
If you have this old perfdata you can generate old private keys and take the balance.
Seems like the only way to steal funds from these old addresses.
I considered this possibility, studied the source code of the original application, looked for generator errors.
But I got tired of it, but apparently it is worth delving into it.