I'm sure most "technically-minded" people will be well aware that a desktop would offer better performance. I'm equally sure portability does play a big role in taking or issuing a laptop for most people. Kinda hard to take a desktop along for wfh days or travel...
Besides, the Apple Silicon ones do come out first in tons of benchmarks and the thermals of the 16" ones have received a lot of praise. There may be some desktop-in-a-laptop-shell monsters that outperform them, but for most workloads a 16" M1 Max should be very hard to beat. I have a M1 Pro from work and it's a beast, does a bunch of stressful things a lot faster than my built-from-scratch desktop (not brand new but also not ancient). Maybe read up on Apple silicon and Macbook thermals, a lot has changed since 2018.
My honest complaint isn't even with the Macbooks. They are not that bad, just overpriced, unless you consider the "enjoyment" (a.k.a vanity) of a product aesthetics worth spending money on. In the same way many people buy performance sports cars only to drive at speed limit 99% of the time. Besides thermal throttling, there are plenty of issues afoot that simply don't exist compared to a laptop with well supported linux hardware running a lightweight distro.
The problem is that the general myth of them being "top tier", which solely comes from aesthetics because they will fail any comparable real world use case test against comparable options, causes them to be so prevalent with developers. Take every single Amazon developer for instance - each of them has a private VM "dev-desktop" for development, because while all the services people develop run on AWS in a Linux environment, they want to be an attractive employer and bling out their developers with an MBP.
So now instead of the correct solution of just issuing everyone Linux laptops (and before you say that its not a reliable solution, consider that you are saying that a company that built and runs the behemoth that is AWS can't hire competent dev ops/it to provision Linux on developer laptops), they waste way more resources, internal tooling sucks (they have a tool that basically rsyncs directories over ssh just so you can develop on your mac), and causes additional issues due to incompatibility of some JNI native libraries, case sensitivity of the file system, e.t.c.
Besides, the Apple Silicon ones do come out first in tons of benchmarks and the thermals of the 16" ones have received a lot of praise. There may be some desktop-in-a-laptop-shell monsters that outperform them, but for most workloads a 16" M1 Max should be very hard to beat. I have a M1 Pro from work and it's a beast, does a bunch of stressful things a lot faster than my built-from-scratch desktop (not brand new but also not ancient). Maybe read up on Apple silicon and Macbook thermals, a lot has changed since 2018.