So I have a theory about the removal and return of Magsafe and SD card reader. They were removed at the same time that the Touch Bar was introduced, so I believe the cost of including the Touch Bar heavily influenced the decision not to include Magsafe and SD card readers. Apple knew including all three meant raising their price points needed to hit their margin goals, so something had to go. They mistakenly thought the value of the Touch Bar would be much higher that it was to most customers, so they thought it was worth the high cost.
I'm also wondering if thats why the 2016 redesigns always seemed to skimp on ports, and didn't include any USB A ports, where they were trying to save a few bucks everywhere they could to pay for the TouchBar.
Now that they are removing the TouchBar's high cost they have plenty of margin at their target price points, so adding back more of these features makes sense. Probably too late to throw in a USB A port though
And in fact, their margins have to have improved significantly due to the M1 SOC. It's cost has been estimated at roughly $60 a unit (based on comparisons to A13/A14 rumored costs), while Intel was charging Apple roughly $200 to $300 for mobile CPUs. How accurate those costs are can be debated but clearly the M1 is significantly cheaper to make than Apples cost on Intel CPUs. We know that because of the low pricing of the M1 Macs (MBA & Mini $100 cheaper).
So my speculation is the low M1 cost is going to allow Apple to do two things. First, lower their entry level pricing over time to grow market share. Though Apple is unlikely to go too low, I don't expect Apple to start offering a competitor in the sub $500 laptop market given the significant quality trade-offs they require. But I would not be surprised to see a $499 Mini, and a $799 rebooted 12 inch MacBook. Apple's unit cost of the M1 is just going to decline over time as they pump out massive volumes, but it's performance levels will remain excellent for entry level Macs for years to come. Even now it's everyday performance continues to improve as more and more software goes native.
Second is using that extra available budget to going back to offering more premium features and proprietary differentiators in their mid to high end MacBooks. No reason they shouldn't all still include touchID, even if the TouchBar is gone. They should go from skimping on ports to matching segment leaders in USB C ports and offering the highest transfer rates. Even with the MagSafe adapter I expect the USB C ports to also allow charging. May allow the use of more expensive materials that offer advantages in strength or weight (titanium again?), and better keyboard/monitor/SSD components. I fully expect MacBook Pros to fully regain their crown as the undisputed best laptops in the world (a crown they tarnished with the scissor switch keyboard debacle and 2016 defeaturing).
It's likely going to be a great time to be an Apple hardware designer the next three years. Not so much an Intel or AMD laptop designer, where corporate is likely demanding you skimp on ports/features/design because now it's almost impossible to match MacBooks pricing at similar performance levels.