... It was the technology.
So speaketh the Astros.
https://www.newser.com/story/286921/astros-stars-execs-apologize-for-cheating.html"When technology gets as advanced as it has become, the boundaries seem to change," said GM Baker, brought in to replace the fired former manager. "The guys said what they did was wrong. Hopefully baseball can help clean up the game and control the technology so this doesn't happen again.”
So, although the rules as currently written clearly prohibit doing what they did, the Astros' argument is that it wasn't their fault, it was due to the fact that "baseball" didn't control the technology adequately.
IMHO, "baseball" could start cleaning up the game by stripping the Astros of their world series title. Either declare the opponents the winners or (better, IMHO) declare the title vacant due to cheating for that year.