The boring but true answer is that the only thing people should be protesting for is a change of the electoral law. Everything else is downstream of that.
In the US, it's a de-facto duopoly on power, held up by a number of "winner-takes-all" rules. Politicians of either party will do everything in their power to keep "outsiders" (i.e. people/parties that are not entrenched in the two-party system and might actually drive positive change) from ever gaining a foothold.
In Germany it's the famous 5% rule that virtually ensures that every new party must maximize populism or perish.
I'm sure it's very similar in most other "democratic" countries.
Laws aren't perfect. In fact they often are buggy as hell. The electoral law is certainly no exception. However it is ultimately the law that matters most as it determines who can raise to power and who can't. Ensuring it fair and democratic should be the #1 civic duty.
IMO the 5% rule is pretty good.
Otherwise we would have loonies like the Grey Panthers (old people party), the “Spiritual Party”, or the extreme right-wing “Republicans” (AFD is moderate compared to those) being able to vote on laws etc.
Of course that also cuts out some parties that I have supported in the past, but the system allows a lot of parties to participate that aren’t _that_ populist (e.g. the Greens, the Left, the Pirates (I think they managed to get a seat or two in the past))
Of course it’s not perfect, but I still think it’s one of the best flawed systems we came up with so far. We should keep iterating on it but very slowly and carefully.
I'm not sure "keeping out outsiders" is a bug. The US is experiencing what it is like to be governed by an outsider with no previous political experience and who thinks things like "laws" don't apply to him, and who thinks experts can't be trusted and puts unqualified people in charge of the military, science and health. Politicians need to develop -- they should start with a local position, and "graduate" to a national-level position before they even attempt to rule a nation.