I found the sound effect of that train when it first appears absolutely hilarious. It wasn’t the traditional krayt dragon sound (as heard in the '77/'97 versions of ANH or The Mandalorian), but rather the “krayt dragon” call from Ben Kenobi as heard in the 2011 BluRay. That absolutely ridiculous fucking sound, like someone doing a Michael Jackson impression in the restroom three stalls down.

I take this as a retcon. The OOT version of Ben’s call is indeed a krayt dragon, and the 2011/2019 version is this train.