On the other side, political parties are a bit what you demand, just on a more abstract level. At least in Germany, we choose them for their specific answers to our questions (or should do it that way), and then hope that they implement them. Though, in reality, politic is complicated and full of compromising and accepting reality. So it's not always possible or good to actually do what the crowd demands.
While it's true that most countries should use more democratic power from their citizen, the unsolved problem is how that can be implemented in a good way which would not harm the country long term. See Brexit for a case where this completely backfired. Or the ending of atomic power in Germany, which now backfires because the country can't stop coal mining.
The main reasons: First, direct democracy is very vulnerable to populism. Easy slogans that prey on emotions are prone to win against more realistic attitudes. Second, it's very easy to manipulate direct voting. The way you ask can practically determine the outcome. We know that from opinion polls where seemingly very similar questions can lead to totally different results, based on small details or how many choices there are. There are many ways to prevent this in opinion polls, but these would not work in an adversarial political setting. Third, many decisions require expertise that cannot be put into simple questions, and the general public will not have the expertise. In Germany, many members of parliament are surprisingly well qualified in certain areas like tax and defence politics. These are the "backseat" members voted in by party lists, not by direct election. Giving a direction and letting these experts figure out the details later works better than asking for concrete decisions that cannot be later corrected (because they are, as you say, legally binding). If you let people decide about the same issues directly, they will most often not even be able to distinguish between suggestions that are feasible and those that are imaginary. Again, the populist who provides the easy, though entirely imaginary "solution" can easily gain the upper hand. Direct democracy is also more vulnerable to disinformation than representative democracy. This also happens in party programs, of course, but the representative power structure kind of dampens the negative effects from it. Finally, representatives are ideally able to take on political responsibility (and sometimes indeed do), i.e., resign from their post even if a mistake wasn't their personal fault. No corresponding concept of political responsibility exists for the suggested technocrats. Moreover, once a policy decision is made, putting it into place requires a long series of more or less political decisions, too. You cannot just hand over those smaller political decisions to experts.
My 2 cents. Of course, this doesn't preclude discussing how much direct democracy one needs or wants. But I personally completely reject any suggestions for radical direct democracy (which every new radical party invariably makes for a while).
I vote green/left, although they tax me higher, because I think climate change and social justice is more important than whether or not I have 1k per year more or less.
Cue Jeff Bezos getting a tax refund.
Having to consider every minor political issue would be the opposite of what I want.
I agree that maybe some middle ground could be better, though. The parties are too coarse grained, there is no party I agree with on all points. I suppose others feel the same.