I’ve tried making your argument and think the game would be healthier if there were a sense of evolution. If offense teams weren’t secret, choosing defenses wouldn’t be a completely blind guessing game. Then offenses would have to evolve to match defenses, etc.
The bulk of the game seems to believe this blind cat and mouse game is a healthy thing. Part of the prestige of being in a high-end guild is getting access to their teambuilding knowledge. Part of why there’s occasional drama about guild-hoppers is because of the secrecy of that knowledge.
I’ve seen numerous competitive games where the tournaments are played in public and everyone can see the super-secret teams. It does no good for the players during the tournament, because you register your teams up-front and don’t get to adjust. But after the tournament, there’s a flurry of activity as people try to adjust to the new meta. When the games are healthy, each tournament has variance. When they’re not, a few builds dominate. The people who win are the ones that are best at reading last week’s meta and predicting next week’s.
But if you point that out, prepare for the general response to be, “You’re just mad that you’re not in a high-bracket guild”.
I’m not saying the teambuilding is easy or that the high-bracket guilds don’t have higher-octane builds than I’m running, but I will point out the job’s a lot easier when you know nobody gets to see your work.