The only HD drive ever available for Amiga was sold with some 4000 units - a modded Chinon FZ357A spinning at half rpm because nobody at commodore knew how to update PLL circuit in Denise. 1.76MB capacity was reached by not using standard PC format.
Paula being the only chip that had absolutely zero changes from the Amiga 1000 to the 4000. That fact alone is a sad example of Commodore's mismanagement of the platform. Well, except for the CIA which traces its lineage even further back to the C64.
Microsoft itself was shipping software on ordinary PC floppies formatted for 1.68MB https://en.wikipedia.org/wiki/Distribution_Media_Format