...and others inside the organization admitted to stealing opposing teams signs in 2017.

I don't know how many other teams do it, or try to do it, but the quote from one of the pitchers says:

"That's not playing the game the right way. They were advanced and willing to go above and beyond to win."

Apparently other teams were nervous about what tactics the Astros were using and taking advantage of. The Yankees complained about it already in 2019. The Nationals created a new set of signs for the World Series that they had never used before.

In 2017, they had a team of guys watching the catcher from a zoomed-in CenterField camera they had installed. These guys were just outside the team's dugout. When one of the guys could decode the sign in realtime, he would bang a trashcan with a baseball bat super loud. That would mean an offspeed pitch was coming. They made other noises for other types of pitches.

Opposing exectutives have said before, "I don't know what all those banging noises are." I guess we know now.