Under most circumstances I can't imagine a reason to bother powering on a 10 year old system, short of nostalgia. The costs of running it will quickly eclipse the costs of buying something newer and more efficient.
Of course, there are plenty of edge cases, like needing something bare metal that has a particular sort of software compatibility or IO requirements. Some industrial computers still run 486 chips with ISA buses for this reason. These sorts of systems will have been engineered with longevity in mind from the outset though.
Other edge case, just for fun: embedded style systems like the Raspberry Pi. These are tiny, low power, and can be used for specialty purposes for ages. They are also engineered on nodes and setup in a manner that will likely leave plenty running successfully in 10-20 years' time as it is.
It is really only since we've entered the era below TSMC's 7nm node that longevity has become much of a concern at all. It would take a whole essay to even TLDR the constraints of why that only becomes very relevant in the period where those nodes start to become known as "mature", and this is already enough of a tangent, so I'll just leave this breadcrumb of a presentation on the lifecycle of silicon process nodes:
That last one is very significant. The hyper reflective EUV mask mirrors are incredibly hard to make and cost hundreds of millions. The mask alone no doubt raises chip cost by $10 or so.
Likewise, hundreds of engineers for 3-5 years can run up a couple billion dollars that must be recouped.
Of course, there are plenty of edge cases, like needing something bare metal that has a particular sort of software compatibility or IO requirements. Some industrial computers still run 486 chips with ISA buses for this reason. These sorts of systems will have been engineered with longevity in mind from the outset though.
Other edge case, just for fun: embedded style systems like the Raspberry Pi. These are tiny, low power, and can be used for specialty purposes for ages. They are also engineered on nodes and setup in a manner that will likely leave plenty running successfully in 10-20 years' time as it is.
It is really only since we've entered the era below TSMC's 7nm node that longevity has become much of a concern at all. It would take a whole essay to even TLDR the constraints of why that only becomes very relevant in the period where those nodes start to become known as "mature", and this is already enough of a tangent, so I'll just leave this breadcrumb of a presentation on the lifecycle of silicon process nodes: