Use of an orca for a single player without alts

No, he actually has a valid point. It could have been stated better though (key phrase being “do anything with”).

Compressed Ore currently loses value when converting it into minerals. The ore is worth more than the minerals it gets turned into.
justification provided here:

In responce to the OP though, I will say that the orca is well suited for its intended purpose (the transport of ore and moderate fitted ship hulls) It will function as an entry level freighter but once your cargohold value starts to exceed 500 million you need to start examining other more efficient options.