The honest answer to "when should we invest in this" is: it depends on how your buyers already behave, not on how new the acronym is.
A few signals suggest the timing is right now, not later. If your sales cycle involves a long research phase before contact (real estate, healthcare, fintech, enterprise software), your buyers are almost certainly already asking AI assistants comparison questions in your category, whether you're visible in the answers or not.
If your category is competitive enough that ranking on page one of Google no longer guarantees you get chosen, that's another signal. AEO and GEO become more valuable exactly where the traditional channel has gotten crowded.
If you've already invested seriously in SEO and have a reasonably strong content foundation, the incremental cost of extending that work into AEO and GEO is low, and the audit alone (checking where you currently stand in AI answers) takes an afternoon, not a quarter.
On the other hand, if you're an earlier-stage brand still establishing basic SEO fundamentals, technical foundations and core content usually deserve the budget first. AEO and GEO compound on top of a working SEO base; they're a poor substitute for one that doesn't exist yet.
The practical test we use with clients: run the audit first. If you're already showing up in AI answers reasonably often, this is about defending and extending that position. If you're not showing up at all and your buyers are the type to ask AI assistants for recommendations, that gap tends to only grow more expensive to close the longer it's left alone.