Soleimani's funeral was an exception in recent years and it is a great example of the importance of popular support for the perceived strength of a system and its deterrence. It was the funeral of Soleimani that made Trump rethink about further adventures at that point, not our symbolic attack on Ain-al Assad. If anything, our symbolic attack on Ain-al Assad was a signal of weakness, but getting united over the assassination of Soleimani sent a truly strong message to Trump at that time.
However, I completely disagree with your second assessment. January protests were even bigger than the 2009 Green Movement. I remember you kept posting figures that claimed the protests were in the size of few thousands, usually in 1-2K range. How did they kill 3K and injure 25K in 2 days if the protestors were that many? Makes no sense.
Keeping a bad regime in power, that has consistently made bad choices without exception, is like allowing cancer to spread in your body because you're afraid of surgical intervention and medical treatments.