UICollectionView has weird separator insets in landscape mode

Here is a screenshot of the app:

And here follows the code: it's a view controller with a collection view with plain list layout and a diffable data source.

It has 1 section with 2 rows.

The 1st row's content configuration is UIListContentConfiguration.cell(), and it has some text.

The 2nd row has an empty content configuration instead.

As you can see, if you run the app, the separator insets are different for the two rows.

Did I make a mistake?

If this is expected behavior instead, is there an easy fix?

import UIKit

class ViewController: UIViewController {
    var collectionView: UICollectionView!
    var dataSource: UICollectionViewDiffableDataSource<String, String>!
    var snapshot: NSDiffableDataSourceSnapshot<String, String> {
        var snapshot = NSDiffableDataSourceSnapshot<String, String>()
        snapshot.appendSections(["main"])
        snapshot.appendItems(["one", "two"])
        return snapshot
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        configureHierarchy()
        configureDataSource()
    }
    
    func configureHierarchy() {
        collectionView = .init(
            frame: view.bounds,
            collectionViewLayout: createLayout()
        )
        view.addSubview(collectionView)
        collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    }
    
    func createLayout() -> UICollectionViewLayout {
        return UICollectionViewCompositionalLayout { section, layoutEnvironment in
            let config = UICollectionLayoutListConfiguration(appearance: .plain)
            return NSCollectionLayoutSection.list(using: config, layoutEnvironment: layoutEnvironment)
        }
    }
    
    func configureDataSource() {
        let firstCellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, String> { cell, indexPath, itemIdentifier in
            var contentConfiguration = UIListContentConfiguration.cell()
            contentConfiguration.text = "Hello"
            cell.contentConfiguration = contentConfiguration
        }
        let secondCellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, String> { cell, indexPath, itemIdentifier in
            
        }
        let emptyCellRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, String> { cell, indexPath, itemIdentifier in
            
        }
        
        dataSource = .init(collectionView: collectionView) { collectionView, indexPath, itemIdentifier in
            switch itemIdentifier {
            case "one":
                collectionView.dequeueConfiguredReusableCell(using: firstCellRegistration, for: indexPath, item: itemIdentifier)
            case "two":
                collectionView.dequeueConfiguredReusableCell(using: secondCellRegistration, for: indexPath, item: itemIdentifier)
            default:
                collectionView.dequeueConfiguredReusableCell(using: emptyCellRegistration, for: indexPath, item: itemIdentifier)
            }
        }
        
        dataSource.apply(self.snapshot, animatingDifferences: false)
    }
}

Xcode 15.4, iPhone 15 Pro simulator, iOS 17.5, MacBook Air M1 8GB, macOS 14.5.