That's a bit unfair to the modern compilers - there's a lot more standards to adhere to, more (micro)architectures, frontends need to plug into IRs into optimisers into codegen, etc. Some of it is self-inflicted: do you need yet-another 0.01% optimisation? At the cost of maintainability, or even correctness? (Hello, UB.) But most of it is just computers evolving.

But those are not rules. If you're doing stuff for fun, check out QBE <https://c9x.me/compile/> or Plan 9 C <https://plan9.io/sys/doc/comp.html> (which Go was derived from!)