I'm all for stripping titles away for this level of cheating...
If you could prove , without a shadow of a doubt, the team won only due to cheating? Sure, I'm on board. Let's use Boston's 2018 run an an example, though -
The signal stealing only works at home. Boston won a total of 108 games that season.
They were 57-24 at Fenway and 51-30 on the road. Runs scored (5.50) and runs allowed (3.99) were almost identical, home / road splits. Pertaining to the playoffs, the Redsox beat the Yankees on the road to advance, the Astros on the road to advance and the Dodgers on the road to win.
This is not to defend or excuse; this is simply to state the obvious. When speaking of a drastic measure such as stripping a franchise of a title you better be sure:
1: The actions are the only reason they won
2: No other teams participating were doing the same thing
Specifically related to the Red Sox and 2018, no one could beat them. They had the best pitching and bullpen, along with a decent hitting team. They were a steady team who did the same thing on the road as they did at home, they basically had the same results on the road. They were not stealing signals in other ballparks.
Pertaining to other teams, this is going to end up exploding in MLB's face because this is the tip of the iceberg. If anyone thinks the Red Sox and Astros are the only teams doing this? Well, it's like thinking Barry Bonds was the only one using enhancements; it wasn't true then, it's not true now.
If passion is removed and it can be proven, sure. Remove the titles.