Using presidential power to alter voting boundaries would be very suspect. Also, I doubt the states would respond well to that sort of federal authority from the executive.
The Constitution says only state legislatures can decide on district boundaries. SCOTUS ruled last year that it's still constitutional if these state legislature pass a law saying that an independent committee should draw the boundaries but only a few states like Arizona and California have this.
tbh it's a huge issue that has been abused by both parties in the past. republicans have taken it to the extreme. they're learning that it was a bad idea now that they have to deal with the sexual predator trump and his crazy rabid fans threatening to not vote for them.
Not only that. But people will vote for the same congressman all the time until that person retires.
The US could be fully democratic because in many cases you can vote for every position in government. But people don't care, or vote the same. This country could be different if people used the power of their vote.