There are several points that need to be made with respect to that illustration, if lent credence:
(a) Strategic Deception: assuming it wasn't disinformation, which it may or may not. I tend to accept the story, as it is after all the same bunch whose economy was collapsing under the stress of their enormous non-stop war-footing. Reagan's credible deployments of counterforce capable armaments, across the Triad, forced the Soviets to revisit their own assumptions, and they realized that he had successfully created a situation of strategic ambiguity. They could no longer count on winning under almost any scenario. And it forced the soviets to spend even more on defensive preparations than on their offensive. zMaking the financial stresses greater still.
(b) Dated: assuming that their old Soviet-era deficiencies have not long since been cured. Evidence of likely curing...the increased state of readiness for their missiles to be launched on warning in the 90's when the Norwegian satellite launch was misidentified as a missile attack and Boris Yeltsin was minutes away from turning the key. A near-miss for accidental nuclear war. While certainly alarming to the degree we dodged a bullet, as it showed the hazard of the Russians decrepit surveillance...and communications... but, it also bespoke a much higher state of readiness than we had thought.
(c) Its irrelevant. The primary issue was always the Soviet First Strike Plan. It was well understood by the Soviet Military... they were the most likely to commence a first strike...look at how e can't muster up the resolve to deal with Iran today. They knew that then that the U.S. would not do so. Hence, their official public policy to the contrary notwithstanding...they intended to punch first. They never seriously expected anything other than a lame second-strike. Their military manuals overwhelmingly preached a doctrine of surprise. And as far as their being capable of that...well, it had us justifiably concerned in our own right. We had no ABM, they did. We had no air defense. They certainly had deployed enough (however effective it was judged) to say that they had one. And finally,
(d)Deterrent Non-Credibility increases Nuclear Preemption Risks. Our non-survivable retaliatory arsenal becomes (for a tyranny such as the Soviets) a powerful temptation in any clash with the U.S. To the extent we followed the Jimmy Carter/Paul Warnke/Harold Brown view of the feebleness of the Soviets, and deployed minimally, in accordance thereto...the more likely the Soviets would assume the worst...that the U.S. in desperation intended the first strike, since our deterrent in reality would not be as credible to them, as it was in our liberal's eyes. This suspicion thus would place the Soviets on more of a hair-trigger posture than otherwise. Maintaining a credible triad, ended these kinds of speculations on their part...while convincing them of the futility of their own arms race. Donald Rumsfeld's old strategic response approach to the Soviet deployments was vindicated....by Reagan and Caspar Weinberger's Administration.