> An argument I heard recently against this is, if abolished, politicians won't have incentives to campaign in rural territories, and they won't be accountable to rural territories.

I don't see a problem with that if we confront and dismiss the notion that certain individuals (e.g. individuals who live in rural areas) should have more political influence than certain other individuals (e.g. individuals who live in urban areas).

Something as arbitrary as the amount of unpopulated land around a person's home should not affect how much political influence that person receives.