I think that, in the history of the world since guns have been invented, they have mostly been used to the advantage of the powerful, not the powerless.
That is true of, I think, literally everything. Powerful people get first pick of things and go for higher quality so everything advantages them more than others. Modern powerful people are the most powerful in history thanks to technology.
But guns are an equaliser. If powerful people let situations get too out of hand the personal risk to them is staggering. Guns make political or revenge-based assassinations relatively easy in a way knives do not. Arguably that is a bad thing, although experiments like the US suggest it is good in practice.
There's a quote about that by Hillaire Belloc:
https://www.goodreads.com/quotes/355429-whatever-happens-we-...