Not to anywhere near the same extent. The range of power consumption of residences probably covers less than an order of magnitude. The range of bandwidth consumption of residences probably covers several orders of magnitude.
> how do power companies solve it?
By charging people for power consumed, directly. Power companies don't have flat-rate, unlimited-use plans. Everyone knows that if they use more electricity, they pay more, and if they use less, they pay less.
> if they don't people complain, loudly.
Yes, because electrical power is a necessity in a way that Netflix-level internet bandwidth is not.
> I do not believe that consumer internet should be sold via lines that are contended to the point that "brownouts" (that is having bandwidth of < subscribed rate) are a normal occurrence.
ISP's do have customers that get that kind of service. Those customers are called "businesses", and they pay significantly more than residential customers do, because they insist on actual service level guarantees.