Starting sign up for Medicare.

[usonian]

3. I heard a rumor that login.gov is losing its "juice", but both are still in use.

This site compares the two.
https://www.whoshipsapo.com/id-me-vs-login-gov-understanding-the-differences/

I'm afraid that this is the best advice available: (meaning it's ambiguous)

Which One Should You Use?

• If you need to verify your identity for agencies like the IRS or VA, you may need to use ID.me due to its document-based verification process.
• If you require secure login access to multiple federal agencies without additional verification steps, Login.gov is the preferred choice.

Both ID.me and Login.gov play essential roles in securing access to online government services. While ID.me provides advanced identity verification features, including document-based verification and video chat, Login.gov offers a simpler, government-managed authentication system focused on privacy and ease of access. Choosing the right platform depends on the services you need and the level of identity verification required.