Swift: Accessing sections when using diffable data sources?

Question

I have a collection view with multiple sections and eventually multiple cell types. I've read that we should avoid using indexPath with using diffable data sources. Is the way I currently access sections defeat the purpose of using diffable data sources?

private func generateLayout() -> UICollectionViewLayout {
    let sectionProvider = { [weak self] (sectionIndex: Int, layoutEnvironment: NSCollectionLayoutEnvironment) -> NSCollectionLayoutSection? in
    guard let self = self else { return nil }
    guard self.dataController.sections.indices.contains(sectionIndex) else { return nil }

    let section: NSCollectionLayoutSection
    let sectionKind = self.dataController.sections[sectionIndex] // This is the line in question
    switch sectionKind {
    case .food:
        var configuration = UICollectionLayoutListConfiguration(appearance: .plain)
            section = NSCollectionLayoutSection.list(using: configuration, layoutEnvironment: layoutEnvironment)
        }

        let headerFooterSize = NSCollectionLayoutSize(
          widthDimension: .fractionalWidth(0.8461538462),
          heightDimension: .estimated(26.0)
        )

        let sectionHeader = NSCollectionLayoutBoundarySupplementaryItem(
          layoutSize: headerFooterSize,
          elementKind: UICollectionView.elementKindSectionHeader,
          alignment: .top
        )

        section.boundarySupplementaryItems = [sectionHeader]
        return section
    }

    return UICollectionViewCompositionalLayout(sectionProvider: sectionProvider)
}

private func generateDataSource() -> UICollectionViewDiffableDataSource<HomeDataController.Section, Item> {
    let itemCellRegistration = setupItemCellRegistration()
    let headerRegistration = setupHeaderRegistration()

    let dataSource = UICollectionViewDiffableDataSource<HomeDataController.Section, Item>(collectionView: collectionView) { [weak self] collectionView, indexPath, item in
    guard let self = self else { return nil }
    guard self.dataController.sections.indices.contains(indexPath.section) else { return nil }

        let sectionKind = self.dataController.sections[indexPath.section] // This is the line in question
        switch sectionKind {
        case .gear:
            return collectionView.dequeueConfiguredReusableCell(using: itemCellRegistration, for: indexPath, item: item)
        }
    }

    dataSource.supplementaryViewProvider = { collectionView, kind, indexPath in
        guard kind == UICollectionView.elementKindSectionHeader else { return nil }
        return collectionView.dequeueConfiguredReusableSupplementary(using: headerRegistration, for: indexPath)
    }

    return dataSource
}