The iMac and MacBook Pro will be updated this year, just like every other year for the past decade (with one single exception). The year’s not even halfway over, no need to panic. I’m hopeful the keyboard and touch bar will be improved.
Mac Pro is the biggest hole in the lineup, the new platform coming next year should have been released a year or two ago. Even though market share is low, it’s an important model.
Mini is adequate for its target audience but newer processors and TB3 are overdue. We’ll either get an update, probably including quad core again (or it’ll be canceled) this year or next. It will never be a popular model, even if mini fans had their dream machine. (Because it would be Apple-priced, and users overwhelmingly prefer laptops or iMacs.)
12” MacBook updates will be driven by Intel Y-series CPU availability. Maybe no update this year. Will be the first model to run ARM-based macOS, if Apple chooses to go in that direction.
MacBook Air is sold at a price point and doesn’t need, and will never get, a yearly update. But it’s due to be updated or perhaps replaced with a different platform. MBA could also go ARM at some point.
iMac Pro won’t be updated yearly because Intel won’t be updating Xeon W-series every year. Same with Mac Pro, when it’s released next year. Like macOS, the rumors of the death of Mac hardware have been greatly exaggerated. If Apple wasn’t all-in on the Mac/macOS, they wouldn’t have released the iMac Pro last year or be developing a new Mac Pro platform.
But sure, let’s hear all the concern about Mac hardware, while Apple continues to increase market share against PCs in a shrinking market. Updates will come; of course waiting is really, really hard—especially when updates are imminent.