https://www.britannica.com/biography/Ronald-Reagan/Relations...
"We were all a little more skeptical than American politicians -- the significance and the chances of tearing down the wall, there we were skeptical," he recalled in an interview years later.
"It was not well-received within the foreign policy community or the pundit class," Brinkley said, in an interview with CBS. "Many people called foul."
As Brinkley notes, however, history has been kind to the president's speech.
"It's seen as a turning point in Cold War," he said. "I think Reagan's speech bolstered the morale of the pro-democracy movement in East Germany."
"There was a movement that was growing and building toward liberalization and this gave great impetus to it in the aftermath," added Duberstein. "Even though people in the Soviet Union thought the speech was provocative, it worked."
https://www.cbsnews.com/news/remembering-reagans-tear-down-t...
> In 2014, a declassified CIA paper stated that "In response to SDI, Moscow threatened a variety of military countermeasures in lieu of developing a parallel missile defense system".
The Soviets had very capable scientists who could figure out - like Bethe in the US - that SDI was not feasible, and the easy work-around is to launch more missiles, not build their own SDI.
Or for something more scholarly, from "Did Star Wars Help End the Cold War? Soviet Response to the SDI Program" at https://scienceandglobalsecurity.org/archive/sgs25podvig.pdf Science & Global Security, 2017, 25.1: 3-27.
> The evidence on the Soviet response to SDI that emerges from the internal documents largely corroborates the view that the Soviet Union eventually realized that this program did not present a danger to its security because it could be relatively easily countered with simple and effective countermeasures.
Since gadders' comment is flagged, I don't know the fuller context.
That is, as far as I can tell, it agrees with me ("responses to SDI were not a major factor in either the collapse of the Soviet Union, nor in the end of the Cold War"), including by citing the same source I gave, the paper by Pavel Podvig.