There is no inconsistency if one programs in straight Bourne shell from 1978, not using any additional features, and frankly, I've been programming in it for 25

There is no inconsistency if one programs in straight Bourne shell from 1978, not using any additional features, and frankly, I've been programming in it for 25+ years and never needed "bashisms". ksh is also extremely consistent and portable. One of the main hidden strengths of AWK is that there is one and only one way how to do something in AWK syntax, so from that point, as long as one doesn't use GNU AWK-isms, it's programming luxury and paradise. Programs written in non-GNU AWK run everywhere (one would have to go out of one's way to use Thompson specific features, for example). As far as I'm concerned, it's a matter of understanding UNIX, not GNU/Linux, but UNIX, so that it is clear what is what and what specifically to avoid (like any GNU features). People who grew up on GNU/Linux often struggle with understanding what's what because they have a huge knowledge gap. The fact that GNU/Linux was their first UNIXoid OS is actually highly detrimental now.