IF hum is a problem, adapters exist to convert from rca to Balanced, simply to use a better noise resistant balanced cable for the run.
Using an RCA to XLR adapter does not convert the signal to balanced; the signal will remain unbalanced. As for a noise resistant cable, that’s actually more likely to be an RCA cable. Balanced interconnects usually start with an assumption that they’ll be used in a true balanced circuit, where they’ll benefit from common mode noise rejection.
A phono cartridge is technically a balanced (floating) source. It only becomes unbalanced when you use it with a single ended preamp.