Example: for the credit dept of a now-ex investment bank many moons ago we had a set of blessed (including with the correct correlations) random numbers pre-computed and baked in via code generation.
I discovered that I could actually generate numbers faster at run-time with highly-tuned code because of the high cost of paging in the large-precompiled numbers array across the network.
I am not saying there is no solution to these problem, of course there is. All I said is that it makes bootstrapping a system much harder than it would otherwise have been with constexpr. Many devs avoid those issues because dependencies rarely change and once you fixed all issues, it will most likely stay stable.
Mature and "made for embedded" projects tend to be better since cross compiling have been taken into account in each steps of the pipeline. But if you start pulling random code from the internet, expect the worst.