The decade started at 2010 and finished at 2019, right? If so, then what was the Mac of the Decade? Stephen Hackett:
When the original MacBook Air was introduced, it was positioned — both in price and marketing — as a high-end, ultra-portable notebook that was perfect for those who traveled a lot for work or just wanted the lightest Mac notebook possible.
My view of the best Macs of any year or decade is the same. Whatever Mac is the most recent. 2019 MacBook Air? Great. 2019 iMac Pro? Great. 2019 Mac Pro? Greatest.