Let's Encrypt issues 9M certs per day (https://letsencrypt.org/stats/), and its market share is 50%+ (https://w3techs.com/technologies/overview/ssl_certificate), so I assume there are <20M certs issued per day.
If all certs are sent to just one CT log server, and each cert generates ~10KBytes outbound traffic, it's ~200GB/day, or ~20Mbps (full & even traffic), not in the same ballpark (2-3Gbps).
So I guess there are something I don't understnad?