[bewaretheirs]

Easy to imagine but there are so many details to nail down that it's hard to do in practice.

In the words of someone in the industry who tends to be on the laconic side:

"It is not as simple as a 'common connector'. There are different pressures, mixture ratios, comm gear, seat interfaces, etc. A requirement for commonality flows requirements upstream to the suit, seat and spacecraft. "

https://forum.nasaspaceflight.com/index.php?topic=60593.msg2...

[marssaxman]

I meant it the other way around - incompatibility is the easy-to-imagine default! In absence of some heavily-funded, top-down, NASA-driven standards-development process, no such thing as a standard spacesuit connection should be expected to exist.