My position is not that there aren't good reasons to have not upgraded from a 2015 Mac, or that I'm having trouble imagining what they are, but rather that it's a reasonable question to ask of someone in this specific forum.
They were extending the analogy to make a counter point. That's a good faith thing to do.
I believe that OP's intention was to suggest that professionals who work in fields with high demands for performance, like professionals who are passionate about their work, are likely to invest in new and improved ways of accomplishing their work, even if it's only a marginal gain. (e.g. the marginal gain of moving from Spotlight to Raycast was worth it for me).
Discussing cost controls in Formula 1 moves us further away (IMO) from that universal truth they were trying to cast a light on.
https://www.cpu-monkey.com/en/compare_cpu-apple_m2_8_gpu-vs-...
To put it in fully objective terms, a lot of development tasks (for many people) are still dominated by single-core performance.
The M2 has roughly 2x single-core performance, which is going to be absolutely awesome if you're spending a lot of time waiting for the CPU. But if that's not really a bottleneck, and the things you do are already completing at a speed that doesn't disrupt your flow state or otherwise consume significant amounts of your day.
I'm working (on my 2018 MBP) on some Python software that does science stuff. The single core perf delta between my CPU and the M2 is even smaller for a lot of tasks, more like 50% instead of 100%. And I'm not doing anything that would really benefit from more than 6 cores.
I'm currently planning an upgrade, but it's just not a pressing need as $2K-$3K is a significant investment for me at the moment.