It's a complete fallacy that every program that needs crypto needs to link to crypto libraries. Look at how Plan 9 does it, where everything is statically linked, but it's other processes which do crypto. Replace only one binary, and the crypto is fixed for all binaries.
shared object libraries are exactly that, a special case of an ELF executable. Special, in the sense that they are not directly executable by users on the command line, other than that, there is no difference (as regular ELF executables can be compiled as re-entrant, position independent code just like shared object libraries).
The real difference between static and dynamic linking is self-contained vs. external dependencies. This dependency can be actual "linking" or it can be inter-process; I don't think that changes the equation.
Interesting fact: while not all shared object files are executable (or rather: do something interesting other than dump core), some most definitely are: try executing libc someday: $ /usr/lib/libc.so.6
