oohhhh okay i think i understand now
(i know for CERTAIN ive heard the "open5" sfx elsewhere in official shows that wouldnt risk illegally using a sound effect... namely batman the animated series at least once)
So, if you're correct (and I think you are, like I think I've heard RM sounds in non-RM things that are more mainstream public facing than RM and that could never fathomably be using sounds that originated with a piece of Japanese game development software, but I can't name even one example like you have) I think what has happened is that Kadokawa/ASCII/Agetec/Enterbrain/Gotcha Gotcha purchased a license to use these stock sound effects alongside many other diverse end users (such as, for example, Batman the Animated Series) or purchased the license to use royalty free sound effects (same thing except
Kadokawasciitecbraindegigotcha just pays for the SFX up front). There are
certain stock sound effects that are so widely used across different media that they're a thing. The
Wilhelm scream is probably the best example, and has its own
wikipedia page.
They (Kadokawasciitecbraindegigotcha) then repackaged and sold those sound effects with the RPG Maker software under the RPG Maker software license, I think, and I'm curious if that was permitted by the terms of the license they acquired the SFX under, whether royalty free or not. If they bought the sound effects Royalty Free, that probably has less strings attached with what you can do if you own it, since unlike a normal license, you're not already going to be connected by the process of making royalty payments.
To state the obvious, this is 1,000,000% speculation on my part, I don't actually know anything about this in any real or concrete sense.
Obviously I mean Kadokawasciitecbraindegigotcha has it well within their means now to create sound effects, but was Kadokawasciitecbraindegigotcha set up to actually foley/record their own sound effects when RM2k (or the even more ancient iterations) came onto the market? I know virtually nothing about how sounds can be created digitally from whole cloth (sound, like pixel art, like many other things, I can edit well, I just cannot create from scratch) so I guess that's another possibility, something that would be trivially easy today but might not have been in the early 2000s? Idk. I know I'd watch a documentary on how RPG Maker was made in the first place if anyone made one.
Thunder12 sound effect from VXAce is similar to the starcraft 1 sound effects. I guess some of the were actually available out there during that time.
I also heard several RPG Maker sound effects from time to time in anime. It is very rare though.
Now that doesn't surprise me as Kadokawa is a huge multimedia company quite involved in the production of a whole lot of anime IIRC.