I don't understand this argument: "it's 47 years old" as a bad thing. If something has been around that long, does it not mean it is proof tested?
The syntax of Taskfile looks more verbose to me than Makefile, which is basically a shell script in disguise. To note also is that you praise Devenv because of it being based on Guix (Guile scheme), while you ditch Makefile which also embeds Guile scheme as the extension language (in latest versions).
Also to note, the opening argument, writing Readme files on how to build and use the software, has nothing to do with Makefiles at all. You could write a simple skeleton codegen that generates a Readme file skeleton or a template with those steps autogenerated in any language preferred, shell included, and run it as a Makefile target.
The syntax of Taskfile looks more verbose to me than Makefile, which is basically a shell script in disguise. To note also is that you praise Devenv because of it being based on Guix (Guile scheme), while you ditch Makefile which also embeds Guile scheme as the extension language (in latest versions).
Also to note, the opening argument, writing Readme files on how to build and use the software, has nothing to do with Makefiles at all. You could write a simple skeleton codegen that generates a Readme file skeleton or a template with those steps autogenerated in any language preferred, shell included, and run it as a Makefile target.