And early on it did, but after the initial excitement of the mode decreased over time, less and less of the initial audiences are returning to participate in shadows mode. It isn’t the same as fighting real human opponents, which most likely will have no other mode to compete with it. Online multiplayer is the main catch to which the majority player base is currently invested. If there were larger incentive to return to shadows mode beyond achievement, and drive up the number of players using it more on a daily basis, then by all means, it should work as ideally as you envision it.
However, the truth remains that anyone can make a shadow (or two), but unless you have large numbers of people highly invested in the mode, the number of shadows that exist versus the number of players still using the mode is HIGHLY disproportional. There are far more shadows than users on the mode. Even if you do survival mode, eventually it is inevitable you’ll encounter the same opponents over and over again, but no one thinks about why. The reason is that the Survival Shadow mode is based on tiers of shadows, similar to how they are tiered in the shadow price ranges. You start off against opponents who are in the 50 point tiers, then the 100p tiers, 250, 500, then all 1000p tier opponents.
This is where the shadow survival mode is really flawed, as eventually, since there are very few in the higher tiers to qualify to go into the shadow survival mode, and hence you play the same players over and over. Shadows is actually much more complex in that a really good shadow would require MONTHS of usage and THOUSANDS of match recordings to become a high powered monster.
On top of that, a lot of people also don’t invest in shadows mode yet as their character isn’t yet shadow enabled. I know I’m holding out until Cinder is shadow enabled, but until then I have thunder.
So unfortunately, it isn’t as simple as create your shadow and sit back while watching the challenges come in. Unfortunately, it seems that only those that are easy to find, like top leaderboard shadows, tend to truly be challenged a lot more frequently than others.
To that extent, yes I can agree shadows may be somewhat broken, but until some solution is implemented, I’m afraid that this is the best compromise I can offer. I apologize if it’s not as helpful as you want, but it’s the best I can give you.