Should CSAM/itsme remain available?

Context

With passkeys being introduced progressively, it's worth asking whether CSAM and itsme should eventually be deprecated in favor of a single passkey-based flow.

Options considered

• Deprecate CSAM/itsme over time

  Migrate all members toward passkeys exclusively, phasing out federal identity integrations.

• Keep CSAM/itsme as permanent parallel paths

  Maintain CSAM and itsme as first-class, equally supported login and identity-proofing methods alongside passkeys.

• Keep but hide by default

  Retain the integrations technically but surface them only on request, defaulting every member to passkeys.

Rationale

CSAM and itsme already provide verified, government-backed identity that passkeys don't replace — they solve identity proofing, not just repeat authentication. They also serve members without compatible devices for passkeys. Removing them would create the exact fallback gap this playbook warns against in [Safe fallback design](/patterns/safe-fallback-design).

Risks

• Maintaining three parallel identity integrations (password, itsme, CSAM) plus passkeys adds ongoing engineering and support surface area.
• Members may still default to whichever method they used last, rather than the most appropriate one, without a centralized methods screen.