The most painful parts are (1) it's a bit hot and loud under load; (2) you need to patch modern software like git, likely with little hope to upstream; (3) waiting hours for those "simple" things to compile - which, in the end, tells us something important about what we'd consider "simple" nowadays.
For both retro and previous-generation hardware, security is the most important concern. Patches for PowerPC kept coming until 2011 or so (that's almost 10 years after that particular machine was released). I'd expect the Intel Macs to keep getting official patches until 2030, and in the meantime I wouldn't be surprised to find community efforts to extend that. "Sorbet Leopard" was a thing for PPC Macs, the Hackintosh community is much stronger than back then.
Yeah but they'll be stuck on macOS 26. That's effectively the planned end of that community, they're not interested in running old versions of macOS on PCs.
With Apple reducing the supported models so drastically [0], the OS may also no longer support most of those older hardware-components anymore.
[0] https://www.macrumors.com/2025/06/09/macos-tahoe-compatible-...
I give it ten years until the websites of that community straight up disappear.
People still use PPC Macs to do work: <https://lowendmac.com/2025/skeuomorphic-icons-a-photoshop-pr...>.
People still write new software for System 6: <https://jcs.org/system6c>, <https://amendhub.com/jcs>.
Those are all hobby projects for 20-30yro machines, few of which are left around. There are millions of Intel Macs in excellent shape. Someone will carry the mantle.
That still leaves a perfectly adequate machine for most common uses.