Even though I agree sign stealing has been going on, legitimately, for a very long time, I am also OK with MLB taking a position that you can't use technology to do it. And apparently the Sox only did it sparingly in 2018 and only when they had a man on 2B. Not great, but the minor penalty seems to fit the minor crime.
I would be fine with catchers and pitchers having ear pieces because right now quarterbacks have them and technology is pervasive in all sports. Plus, even with earpieces, teams will continue to study opposing pitchers for "tells" on what their next pitch will be, which is fair.
I believe I read that, in the case of the 2018 Sox, there was ample evidence that ownership had learned from the Pedroia (I believe he was one of the perps) experience of several years ago and emphasized not using technology to pick up signs.