There are historical reasons for the bias in the Senate and Electoral College. Had these biases not been engineered into the US Constitution, the United States might not be the United States.

https://medium.com/politically-speaking/abolishing-the-electoral-college-83ff9ce24a6c

We could argue that these biases are no longer needed today. And there is an amending formula to replace them. But USA cannot seem to find the political will to make these changes.

We could argue that those states who benefit from the bias would not be willing to change. But more importantly, the bias are not overly undemocratic! For example, it is unlikely the EC will elect a president with less than 40% of the popular vote. In other words, the will of the people is expressed reasonable well.

Because the USA tends to have many 50/50 elections, it seems liked coins are being flipped to decide winners. And the EC/Senate bias is one of those coins.