The streamer i use recommends XLR, a lumen. So wtf should you do? I guess you need to buy really good RCA cables to address any deficiencies. And the rabbit hole gets deeper
Of course one of the goals of balanced operation is to eliminate the ’sound’ of cables; if set up correctly a cheap cable can sound every bit as good as an expensive cable. Look at it as a technology that successfully solved the interconnect cable issue (and did so long ago).
There are balanced tube preamps around FWIW. If you want to get the most out of going balanced, make sure the preamp supports AES48, the balanced line standard. If inquiring about this and the manufacturer does not seem to know AES48, it usually means it does not support the standard.