1) lack of competence
2) system
3) grift/bloat

You’re right that some politicians just say things to get elected, but even the ones who mean it have little chance of succeeding, IMO.

First, most lack the necessary competence (and intelligence) to solve problems, much less thorny problems. At best, most are rank amateurs in all fields outside their own, yet they have power over multiple issues that affect us all. This set-up is a recipe for disaster. Would you hire Congress to renovate your house? Why would you hire it to do more complicated tasks?

Second, our government is intentionally designed to have limited power with numerous checks and balances. It’s set up to do…not much of anything, so we shouldn’t be surprised when it does exactly that. It is inefficient by design.

Third, there is a strong incentive NOT to solve problems. Why would Democrats, for example, wasn’t to “solve” racism or climate change when they get so much political mileage out of both? Why would a metastasizing public and private bureaucracy — making billions — want to solve the problem that puts food on their collective table (or pays for a third vacation home), or, money aside, gives them a reason for being? The primary goal of a bureaucracy is to protect and grow the bureaucracy, and that’s why you see bureaucracies growing instead of solving the problem they were created to solve.

So, while politicians lie about what they are going to do, even the earnest are going to find it difficult to “get things done”. We should not be looking toward government as our savior.