Little b vs Big B
Mbps (lowercase b) means megabits per second, used by internet providers and camera bitrates. MB/s (capital B) means megabytes per second, used by filesystems.
8 Mbps equals 1 MB/s.
Why real uploads take longer
A 100 Mbps uplink theoretically transfers 12.5 MB/s, uploading 1 GB in 80 seconds. Real transfers experience Wi-Fi loss, server throttling, and TCP overhead, resulting in 80-90% efficiency.