I bought a used Dell workstation with a 8c16t Xeon E5-2670 and 32GB ECC DDR3 RAM a few years ago. It's a bit outdated now, but it's still faster than the most laptops (for multi core workloads). At the time I had a MacBook Air, so this completely blew it out the water. I remember one time while trying to debug an issue I had 10 docker instances of our CI running (Rails + Cucumber + Firefox) and there was absolutely no performance impact to the desktop experience.

Last year I bought a T470s with 20GB DDR4 and an i7 (U series) as I was mostly working away from home. It's good enough for most of the work I do, but it can be a bit slow at times. The processor just isn't as fast and the integrated graphics struggle with a 4K desktop (I think that's mainly Linux/GNOME being unoptimised though). I haven't noticed it throttling, but my workload usually isn't that CPU intensive.

If you mainly work from home I'd definately suggest building a desktop machine for your needs.