Watches

There's actually a good chance they wouldn't have. Concerns about electromagnetic radiation, actual radiation, battery life, and the general size/shape of G-Shocks (i.e. difficulties with suits/gloves and uniforms, getting caught on untamed undergrowth) would be legitimate reasons for many people in high-intensity employment (e.g. divers, astronauts, pilots, military personnel) to choose smaller watches.

With regards to your "extension" of your argument (i.e. if people today wanted to be like the astronauts of the past, they'd use the pinnacle of the technology available to them, i.e. G-Shocks), that makes a number of assumptions that in some cases are factually incorrect or neglect field-specific considerations, some of which I pointed out in the previous paragraph.

Divers, for instance, do use the pinnacle of technology available to them - dive computers. Astronauts probably have suit concerns when considering watch size/bulk. Modern-day commercial pilots also use the pinnacle of technology available to them, which is the computers built into their aircraft.

As for G-Shocks and quartz watches in general being the pinnacle of horological technology, that's a majorly subjective position, and one open to all kinds of debate. Your argument also assumes that people in the present day, especially in high-intensity fields, wear watches for mostly practical reasons (hint: they do not; the watch is a convenient timekeeping device and a piece of functional jewelry, but in the practice of many fields, not just the high-intensity ones we discuss here, they are not an essential piece of equipment).