I think it's still pretty common if you play a lot of PC games, but it's likely much less so. There seem to be less and less games giving you out-of-the-box developer console access which over time will likely cause new video game players to not know about them as much.
The concept at least is well known by younger generations. There is an entire movie based on the Backrooms YouTube series coming out that is centered around the idea of "noclip."
It’s not an actual crime, but If it’s an online multiplayer game it is a violation of the terms of service. Add to that it tends to ruin other people’s enjoyment of the service, thus negating the main purpose of the service. I think people who cheat in online games are pretty sad, pathetic, and selfish.
Yeah, even in single player today. Can't let the idea having fun in a game or having control over a game spoil the statistics of "achievements" for the Achiever players anymore. (Sigh.)