I made this! Thanks for posting it, I'll gladly answer any questions.
The samples are available here on GitHub: https://github.com/matteason/scotrail-announcements-june-202...
...and here on Google Drive: https://drive.google.com/drive/u/0/folders/172W6sXnvlr7UcNLi...
We crowdsourced transcriptions for all the clips and Simon Willison built an interactive dashboard to explore them: https://scotrail.datasette.io/scotrail/
The announcements are read by voice-over artist Alison McKay: https://www.alisonmckay.com/