> and if those in power use violence against the non-violent it increases public sympathy for them.

Even then there's like a fine balancing line where some level of state violence is "acceptable", as in it crushes the spirits of those out on the streets before they manage to organise enough, and yet doesn't get nearly enough attention or wide-enough condemnation (both within and outside of the country). This buys the regime some time even when they're nowhere near 50% of support, and then the very next elections become even more of a sham than they were before. The regime still magically gets as close to 50% of the votes as possible, while still winning with a wide-enough margin that you have no legal recourse to challenge the elections, which only crushes people's spirits even further.

For post-2019 examples, see Georgia (ruling party won with 53.93% in 2024) and Serbia (has yet to have an election, despite largest protests in its history calling for early elections for the past 15 months).

My point being, to overthrow such a regime via a ballot box, 55% against just doesn't cut it. At the very least you need 70%.