With all due respect, being "from the other side of the pond", I don't think you understand the U.S. well enough to be commenting. For example, California is both the largest producer of food in the U.S., and the state being most significantly under-represented in all three branches of government.
The U.S. is also, easily, the most volatile (extreme partisanship) country of comparable rich, democratic nations. The system we have is pretty unique in its attempts to bend-over backwards to boost rural voters' importance, and we're worse off in virtually every "bad thing" you mention than countries that don't do this.
Centralization? Our president is independently murdering people in the carribbean, demolishing an entire wing of Whitehouse to build himself a new ballroom, independently changing funding (i.e. has hijacked the power of the purse from Congress), is independently sending in the U.S. military into states run by his political opponents against their will, pardoning violent criminals who supported him (one of whom was caught plotting to murder the House Minority Leader, Hakeem Jeffries), etc.
Rural areas will stagnate / people will move away? Dawg. That's already been happening despite the political concessions they've been given. That ain't the problem.
Urban house prices skyrocketing? Happening. NYC is among the least affordable major cities on the planet.
Crime rate? Generally highest in the places where we give disproportionate political sway to.
Are you suggesting the 66x more representation Wyomingers get over Californians in the Senate isn't enough? Is the ~3.5x more voting power they get in presidential elections not enough? What is a fair "middle ground" in your estimation? Because it feels extraordinarily unfair in the exact opposite direction, to me.
(Editing to add): It's also worth pointing out that this delta in voting power is much more extreme today than it was when this system was designed. In the 1800 census, the most populous state, Virginia, had 885,000 people, around 15x more than Delaware, the least populous state. Today, California has 67x the population of Wyoming.