I don't know how to respond to somebody that doesn't understand that. Higher level cards have more abilities and higher stats. Since there are no limits currently the bot does not know what cards your opponent is going to use. It is very simple. It makes it much harder for the bot to brute force simulate which cards to win.

When you put card level caps on, the math equation becomes an order or "orders of" magnitude easier to figure out for the bot or battle helper.

It removes the advantage that humans have over bots. Humans are good at problem solving and summarizing within the context of a problem.
Bots are good at calculating and brute force simulating. This is going to give bots and battle helpers the advantage and modern will get overwhelmed with battle helpers since they are harder to detect.

A developer made a youtube video a year ago about bots in Splinterlands.
Here it is.