"Ranked Competitive" is so players who are really, really into Tales of Tribute can play competitively against other players who are really, really into Tales of Tribute and battle it out to see who's good, who's better, who's best.
"Unranked Casual" is apparently so ranked competitive players who are really, really into Tales of Tribute can play competitively against unranked casual players who are only casually into Tales of Tribute and completely wipe the gaming table with them.
Maybe there should be a third Tales of Tribute queue, something like "Unranked Casual vs. Unranked Casual," and players are disqualified from entering that queue if they having a ranking, or at least a ranking above a certain level? Otherwise, unranked casual players who just want to play a fun, casual match must suffer through half a dozen or more brutal matches with players who are obviously ranked competitive vets before they maybe finally get lucky enough to be paired against someone who's more their calibre.
I've fought mudcrabs more fearsome than me!