But before trying the Terminal settings command in that Reddit thread, I would definitely first try updating to the latest installer. That might fix it.
Thanks all.
Getting the installer updated seems to have made a dramatic improvement.
Using the arrow key selection method outlined in the blog also seems slightly more performant (in addition to just being more efficient and easier - great tip).
Obsidian: Version 1.8.10 (Installer 1.8.10)
macOS : 12.7.6 (21H1320)