I understand the US doesn't have a lot of choice on the ballot, political news is highly polarized and latest/developing news is probably not worth following. But somewhat keeping up with what your government does so you can hold it accountable seems like a civic duty to me. And what better way to do this than news?
That is not at all true. Sure there may only be two parties with one candidate each on the national level (assuming you don't get involved with the primaries), but in the US a lot more local positions are elected (which in many ways have a much greater effect on your day to day life) and local referendums (or ballot initiatives) are very common.
Ballot measures only address a small subset of policies, and they don't exist in many places. From what I understand making a 360 turn on them after being elected isn't uncommon either.
So your 'informed' decision is probably just as biased as someone who bases their decision on news.
I'm not really sure what point you're trying to make. Are you saying nobody can ever know enough to vote responsibly?