I'm still on a Gen 8 i7 (with 40 GB RAM, to boot) T480s. I take pretty good care of my machine, so it's still in superb physical shape.
But, given today's massive webapps and video calls while having my workspace programs open, I'm in Hell. A failing keyboard would probably push me to repurpose the current machine and upgrade as well (and still replace the keyboard for kicks).
If I wasn't strapped for cash, I would have bought an AMD Framework eons ago.
And modern bikes do make with the need for cable replacement or breakage (hydro lines and electric shifting, while more expensive to service, also require much less of it).
My own life tip: there are plenty of good analogies, so no need to choose use an example you are not familiar with.
We all see that OP does understand bikes in the general sense, indeed the fact you are nitpicking instead of trying to explain one of the many fundamental difference means you think that as well.
They're not totally without value but I find that it's generally better to avoid a analogies. Look for some other route to make the point.
They rely on the recipient going along with the analogy and trying to make it work, not trying to find problems with it. If someone understands the concept well enough to needle the analogy, they probably have a better understanding than the analogy can provide anyway, so it is fine to give it up.
In this case it is neither used for arguing, nor for explanation really, I think, but as a bit of rhetorical flair. The analogy is to an obviously stupid thing to do, throw away your bike because of some easy to fix cabling issue.
"My current laptop is an aging X1 Carbon generation 7... A few months ago a few keys of the keyboard stopped working. I decided it was time to look for a replacement."
Isn't that like deciding to replace your bike because some of the cables are rusted? Like a new set of cables, a new keyboard is a small expense compared to a whole new laptop.
Like replacing bike cables, swapping in a new Carbon X7 keyboard might be slightly challenging for an amateur. iFixit calls the keyboard replacement "moderate" in difficulty [1] taking about an hour with a new keyboard running about a hundred bucks. But it would be a simple job for a repair shop. So it seems hard to justify the expense of a whole new one rather than just the new part.
Of course, sometimes you just want a new laptop, because the bike analogy breaks down a little: unlike bikes, newer ones are inherently faster.
[1] https://www.ifixit.com/Guide/Lenovo+ThinkPad+X1+Carbon+7th+G...