This is like asking about the practical applications of chess. They're probably mostly nth-order effects.

Heh, yes, the comparison to chess is a very good one. You probably need a similar level of focus and dedication to be a good Life pattern engineer or a good chess player -- and that level of focus is something that improves with enough practice, in both cases.

I've mentioned in other answers that Life can make a good teaching tool for various mathematical and computer-science topics, mostly because it's entertainingly eye-catching. When you get a design right it's very satisfying -- like one of those huge domino chains that you see on YouTube, except that (for some designs) it keeps on setting itself back up again as it's in the process of falling down.

It's great for generating synthetic data for training LLMs for solving Abstraction & Reasoning Corpus (ARC) by François Chollet. Game of life helps the LLMs with a 2D understanding of the world.

https://github.com/fchollet/ARC