Except it's not the '00s anymore and most emails don't come from personal gmail accounts. Almost every single email that people receive are automated ones that come from corporations.
Total people using email (2024–2025): about 4.5–4.6 billion.
Google (Gmail consumer + Google Workspace): ≈3.0 billion active users/mailboxes.
numbers from perplexity, but probably good enough for casual conversation