Honestly the amount of time I've saved just by throwing stuff into a text editor with multi-cursor support is kinda unbelievable.

Yes, this is the right thing to do very often, especially for one time tasks.

It’s not the thing you should do if you need to do it repeatedly, like once a day or even once a month.

This all depends on a lot of circumstances, and its hard to calculate time for implementing a script vs doing it by hand for a future you don’t know yet.

I often do a similar thing using emacs macros (I assume most good editors have a similar feature)

Step 1 - Let me try using command line magic to transform this data Step 2 - ?? Step 3 - Create a scratch file in IDEA and some cursor + regex magic and I am done!

And those regexes are the first part of an awk script or something similar which will save time when you want to do this repeatedly.

And when your awk script grows into something that doesn’t produce the final output, but has to be run in another interpreter first in order to produce the final result, then you created your custom language.

Oh sure, if it's absolutely trivial then bash it (hah) through some shell scripts or even just do it on the command line. I'm talking more about things that are slightly more complicated and will need a bit more effort than find & replace.