The team has stated several times on town halls that it is hard to catch people using battle helpers.
Putting the league level card caps back in will make battle helpers super effective because battle helpers use brute force simulations to figure out what cards will win.
By removing the number of winning card combinations with card level caps it makes it much easier for a bot or battle helper.
Please watch Games on the Block video that breaks down botting in WEB3.
This will be a candy jar for scholars that use their profits to make multiple accounts to cheat ranked.
Interesting take. Will look into it in more detail.