As fun as the template contraptions can be, is anyone realistically compiling C code with the abstract C machine from the standard as their target ?

All other things being equal, I guess it's a plus to conform to the letter of the standard, except they are not.

It's much more productive to pick a few practical compilers/architectures as your target and allow yourself to work within the assumptions they provide you.

I'm sure some people will disagree but I'd much rather enable no-strict-aliasing and be on my way than trying to figure out if I actually abide by the convoluted standard rule, since, after all, it does not mandate the existence of this option.