From this piece in The Hill by Steven Lubet:

Adding members to the House will only increase partisanship and feed extremism, as the behavior of state legislatures has amply demonstrated….

Smaller districts would theoretically bring representatives closer to the people, but comparisons to earlier eras do not make much sense. Newspapers were delivered on horseback in 1788 when the first congressional elections were held. In 1929, only 40 percent of American households owned a radio. Today, social media and smartphones have made constituent communication easier by orders of magnitude. …

Allen argues that continuously enlarging the House will “get our politics working again,” but she fails to reckon with the virtual certainty of partisan gerrymandering. Smaller districts would be an invitation for state legislatures to redraw U.S. congressional lines for political advantage, with ever greater opportunities to “crack and pack” minority party voters. …

But as the experience of state legislatures shows, smaller districts do not bring greater democracy or enhance minorities’ access to power. Congressional gridlock has become a dangerous problem, but adding legislators is not going to fix it.