We currently are, but not really. A gigabyte is 1024 megabytes, and a megabyte is 1024 kilobytes, etc. However macOS and hardware manufacturers use 1000 instead of 1024 to calculate storage space. So you could say Apple uses the metric version of storage and Windows uses the imperial version.
1 KiB is addressed by exactly 10 bits.
1 MiB is addressed by exactly 20 bits.
1 GiB is addressed by exactly 30 bits.
1 TiB is addressed by exactly 40 bits.
1KB is addressed by 9.9657842846621 bits.
1MB is addressed by 19.931568569324 bits.
1GB is addressed by 29.897352853986 bits.
1TB is addressed by 39.863137138648 bits.
Bitrates complicate this, because they predate modern computing. It's information theory. Radio signal transmission genuinely can measure in partial bits. And all bandwidth is described in plain metric prefixes.
So you can have an 8000 kbps video, lasting one second, and it weighs 976 KB.
Technically a gigabyte is 1000 megabyte. Megabytes are 1000 kilobytes and kilobytes are 1000 bytes. Which are all proper metric units but sadly don't make any sense. So datasystem manufactures and computer generally calculate with their proper counterparts that you mentions gibibyte mebibyte and kibibyte which sre actualy 1024 of their previous ones. Small but crucial difference.