My question is, any guesses as to how long I can keep running Sierra or High Sierra on the newest Macs???
One caution, running Sierra or High Sierra on the newest Macs (I assume you mean 2020 Macs) might be difficult or impossible to do. I have read that macs can't install an operating system older than the one it ships with due to lack of drivers. So a 2020 MBP can only install Catalina or newer. Others with more experience might know differently.
I recently decided to buy a used 2015 15" MBP rather than a 2020 16" MBP for a number of reasons, the main ones being the lack of useful ports in 2020 and also because I want to stay with Mojave and not go to Catalina. I too have some legacy 32 bit apps which will run on Mojave but not Catalina or Big Sur. I totally agree it's unfortunate that apple insists on pushing us to a future we don't necessarily want. It's been that way for a long time. And then there's the steep price increases over the last few years...
Thanks, kfraser, that was precisely my concern. Then again, Apple has never made it easily to go back to older OS versions. We have some pretty tricky techs here in Bangkok, though. If the new processors will support 10.12 & 10.13, it can happen.
Honestly, I never look to find out if an application is 32bit or 64. I don't really even know what that means nor care. But I like the weird little third-party apps & utilities to keep me running.
I love my 2015 MBP but I loved my 2011 17-inch more! Real estate. I've been meaning to bring my 15-inch into a Mac dealer to compare its size to the 16inch. My eyes are old & I'd like my Mac with Retina.
That said, I've had the 15inch top case replaced twice due to battery swelling. The 17inch was was more problematical: three videocard repairs, batteries, and so on.
I've been dithering about repairing my 17inch, again. I shouldn't dither. New keyboard & battery are less than C$100 and I'll have a Mac I like. In the interim, bought my wife a 2019 13inch MBA. Runs Mojave & I definitely don't want that step up on my own machine. Quirky, I guess you'd call it.
I don't really care about upgradeable. I buy what I need. But the ports are important. No USB?!? WTF! And as I type this, I'm looking at the warming amber glow of my Magsafe. USB-C is a poor substitute. The Magsafe was a brilliant idea.
One may buy a big lunk of expensive third party equipment to attach to the side of the new MacBooks. Looks to me like those USB-C male connectors could be bent or snapped off PDQ.
Yeah, size matters. But not so much on a real Mac.