This point is always brought up but is never argued to its natural conclusion.
On the surface it seems you are implying that citizens should have powerful guns so they can threaten and potentially kill police officers trying to do something despotic. However if someone did that, the police would just crack down 10x as hard on that individual with more powerful, government purchased guns and arrest them for life. No matter what guns people are allowed to have, it's not a deterrent against despotism on an individual level.
The argument that the point of the 2nd amendment is for the citizenry to defend against government power is ridiculous. Why would a blueprint for a government install protections to make sure it can be violently overthrown, when the rest of the constitution is entirely focused on ensuring the consent of the people is funneled up to government power in a non-violent matter? To argue that that's the point of the 2nd amendment implies the founders didn't believe that the Constitution would be effective in forming a representative democracy.