Google’s John Mueller said that changing from www to non-www for your domain shouldn’t change much. I suspect he means that doing that wouldn’t hurt or benefit your rankings that much and Google will likely pick up on the change and the rankings would not suffer much from the change.

John was asked:

John responded on Mastodon:

In general, changing from HTTP to HTTPS or WWW to non WWW, these types of changes, Google is very quick to pick up on these changes and rankings should not suffer from those types of changes. It is when you change some URLs, URL structures and parts of your site that Google is slower to react with.

Forum discussion at Mastodon.