The issue is Apple stops supporting them with updates fairly quickly and plops them into legacy/obsolete rather fast so you can't ever get them repaired.
The thread is about software/OS support, not about the hardware. Other than the solid design of the carbon x1 Thinkpad I would take a butterfly Mac over the trash that's Probooks, Dells and so on any day. Well, with the exception of the 12" Macbook of course which was truly terrible hardware and quality. I've had plenty Windows laptops, I had good reasons to switch to Macbooks. Lenovo is the only laptop manufacturer other than Apple that I'd even bother trying these days. And unless you buy their most high-end device, the rest of the lineup is underwhelming.
I had a 2016 MBP as well that had its share of issues yet it was taken care of well enough: Flexgate a couple years in, free repair outside warranty, issue did not come up again and still works. Battery works, the T keycap broke off, replaced it with a 3rd party one, otherwise no keyboard issues, one USB-C port is loose which was common for the early Apple USB-C ports, so the device only has one left. Other than that port the device works just fine 7 years down the road.
And for one of the worst laptops Apple ever made, if I had just the choice between that butterfly Macbook and a Windows laptop, I'd choose that Mac again. Back then the Thinkpads weren't that interesting that I'd seriously consider them, I had a T420 before that and it was just fine, but in no way equal to the Retina Macbooks of the time. Worse housing compared to unibody, much, much worse display.
Anyways with no updates from apple, you're running the risk of significant security updates. Its not a question can your use a Mac for 10 years, is really should you?
OP said non-professional use. You can do light office work and check your e-mails and calendar just fine on a 8+ year old Mac running Big Sur or Monterey, and watch some Youtube. What security issue exactly are you expecting? You will indeed lose out on XProtect definition updates, so if you are someone who downloads many new apps from random websites you are at risk of installing malware for sure. But the reality is that even the latest MacOS doesn't recognize them all, so if you enter your admin password to install some new random app you are still at risk of malware infection with the latest MacOS today.
Even if the risk is a bit lower, running the latest OS doesn't help much in compensating for such bad security habits. If there is a scam that tries to get the user to enter their admin password willingly to run malware (which is one of the most common ways that MacOS users get malware on their Macs!) MacOS doesn't stand in the way.
Many of the critical flaws that get patched regularly with MacOS are not actually affecting most users if you look closely. For example, most of them require physical access to the computer. And if an attacker has physical access to your Mac then they're probably robbing your place and you got bigger things to worry about than OS updates.
Again, we are not talking about running your business off a 10 year old device out of support or anything like that, storing confidential customer data and whatnot. That would be an entirely different beast and obviously you can't do that on such an old device and still comply with security best practices and laws/regulations.
Installing Linux doesn't actually make the Mac much safer than MacOS, the only difference is that a lot of the malware out there isn't programmed to run on Linux, that's the only benefit it has. For non-technical users Linux is actually not that benefitial, Linux expects you to know what you are doing if you have an admin account. It will happily let you rm -rf the linux OS itself if you want to do that. In that sense even an old Monterey that boots of an immutable OS snapshot has more safeguards in place than the latest Linux.
Yes, and intel based MacBook still can run Linux, M series after 5 to 7 years is just dead.
Unless you have a crystal ball you cannot know how long these Macs will run the latest apps. Again, the 2015 MB runs the latest apps on Monterey in 2023. And it will continue to run these apps for a couple more years, giving it a lifespan of 10 years and for non-professional use you can keep using it for 2-3 additional years before the software really gets out of date. And even then, even after 12-13 years, that Mac can still do simple tasks like managing e-mails, calenders, and light Office work.
If that's your definition of a Mac that's "dead" then sure, super dead. Runs all the latest apps on the fantastic retina display but clearly it's "dead".
