Real reason without salt? Its important to consider they havent 100% said that they wont, so it's not out of the question, but theres a few really important things to keep in mind.
When something has such a low skill ceiling then there isn't really any variety since it isn't PvP. The bots were literally silver level, that's why so many people got bored and don't want them back. The bots were only difficult to fight and 5v5 in the first few games before people knew their abilities. Every game was either just getting multiple kills in lane and killing them every single time that they got to lane or people doing the other ways to win. The only difficult bots were galio and malz because they were actually difficult to kill.
It seemed like it was hard to lose a straight fight to them as long as you just attack them. There were plenty of ways to just abuse their AI by simply fighting them, like I already explained.
You could just run at them and sometimes they wouldn't fight back and they might've start walking away. Well what I meant by exploit wasn't just through ignoring them or split pushing and all of the other ways.