Great. Even accepting your case (I assume you mean the US revolutionary war, which, for the record, I don't think is that great of an example to begin with), you provide a n=1 in support of your argument.
On the other hand, there are literally dozens of examples of civil society organizations organizations and protest movements successfully countering government overreach or military coup d'etats with peaceful means and bringing about profound political change:
While armed resistance against injustice can sometimes be effective (and certainly not all peaceful movements succeed), there is well established qualitative and quantitate research that violence comes at much higher cost (in terms of life lost) and risks (to subsequent democratic and evononomic development) than peaceful resistance. Erica Chenoweth is one particular scholar worth checking out in that regard: https://www.ericachenoweth.com
It makes sense if you think about it for a second: resisting violently against tyranny requires you to build up systems of violence (duh!). Those systems have the tendency to stick around, even if you are successful in removing or fending off tyranny.
You can see this live in the US, if you are willing to look: Tens of thousands of people die every year solely because the US treats firearms differently from the entirety of the rest of humanity. At the same time, the US does not seem to be uniquely resistant to the undermining of democratic institutions, as Trumps current antics demonstrate (this should hold true no matter which side of the Trump/Democrats divide you sit on. Both sides claim that the other is (successfully) undermining democracy).
Peaceful protests, even if they’re successful, have nothing to do with the discussion of “Trying to guard against tyranny by increasing private gun ownership is dumb“
The entire argument for private gun ownership to guard against tyranny is that it is effective and more so than other approaches. If private gun ownership is not more effective against tyranny than other approaches, why accept its considerable and provable downsides (gun crime, gun-assisted suicides, domestic violence, accidents, etc. etc.)?
But peaceful resistance (which goes beyond protests and can – depending on situation and definition – encompass everything from sabotage to strikes, espionage, boycotts and "Work to Rule") has been demonstrated to be more effective to both establish long-term democratic rule, as well as safeguard it against authoritarian rollback, when compared to violent means.
There simply is no actual argument based on historical facts that widespread civilian gun ownership is particularly effective at establishing democratic rule or deterring authoritarian tendencies. Which makes sense, because (again) guns are only good at projecting or threatening violence and authoritarian actors (in contrast to democratic ones) are quite comfortable with violence.
Worked once