The probably most negative meaning of a carrier is the one that carries disease from one being to another. But is it really? Sure, such a carrier might make you sick, but at the same time it also carries the information that helps your immune system to develop a counter measure against the disease.
Humans were not even the first carriers, because ants already learned to carry materials way before that. And even though we invented the wheel, even using that as a first carrying tool was not a humanity first thing: Probably some human looked at a dung beetle in awe and wonder, and then realized that he could replicate that form of external carrying to lighten the load on his back.
Over time carriers have evolved from the physical to the mechanical, and then to the energetic and informational. Even information carriers went through an evolution: starting with clay tablets, papyrus, and paper. Later information became multimodal, and aside from written information we needed to transport sound and vision to others. That too evolved: initially copper wires carried information from A to B, later humans developed the means to record information, on wax cilinders, metal wires, then tape, in reels, cassettes etc.
A similar development happened across information carriers in general: with the arrival of computers we learned to encode all forms of information into bits and bytes, and where the actual carriers went from magnetized ferrite beads to tape, then disc, and of course eventually to chips. And with that, information density is always growing. Even beyond that, artificial intelligence is now compressing knowledge to a level achieved never before!