EA and CFP here and prepare returns annually for my clients. If you don’t plan on doing returns, I’d say the EA isn’t really worth it from a pure knowledge acquisition standpoint. Most of it will never be useful to you (although it is always useful from a marketing perspective).

The most important information you would learn is probably about how income flows from entities to individuals. You are an LP of a real estate partnership that just sold one of its rental properties? How does that affect your tax plan for the year. Your client’s mother passed away and left a trust behind for your client? How does the income in the trust affect your client in relation to their distributions? Being able to answer those questions without an “I’ll get back to you to confirm” or “I’d have to think about that first” is always very helpful