The 6502 was pretty fast little chip: https://imapenguin.com/2022/06/how-fast-can-a-6502-transfer-memory/ https://imapenguin.com/2022/06/how-fast-can-a-6502-tra

The 6502 was pretty fast little chip: https://imapenguin.com/2022/06/how-fast-can-a-6502-transfer-memory/ https://imapenguin.com/2022/06/how-fast-can-a-6502-transfer-... The ARM team decided to design their own CPU because they felt that the available options weren't that much better than the 6502 as they wished them to be.