2400 were 300 bytes per second
(though it might be that 9600bps worked at the 'official definition' of 2400 baud but nobody advertised it like that)
Of course you're correct and a 56k modem is something like 8k Baud, but in marketing the bigger number usually wins
And up until the 2400bps modems IIRC bauds and bps were interchangeable
