Nearly every core step now has an online route. The Social Security Administration accepts name change requests online in most states. Global Entry and voter registration are fully digital. Banks, employers, and insurers accept uploaded copies of your certified marriage certificate. The DMV is the notable exception, and it is a single visit — not a mailing campaign.
A kit optimizes for paper because paper is what it can sell you. We optimize for the shortest legitimate path to a fully aligned legal identity.