I recall that he consulted for an unofficial (semi-official?) concept video by the Roddenberry Archive that was a finale/sendoff for Captain Kirk: https://www.youtube.com/watch?v=mgOZFny7F50 . If you're a fan of TOS, it's worth a watch.

Yup, I am a fan and watched that concept video when it came out. I'm hoping he makes some sort of return, perhaps involving the Star Trek Picard Season 3 reveal that Kirk's body is being kept on ice at Section 31, on Daystrom Station. I would imagine that there are many ways that Kirk could be brought back, perhaps Kirk's body could have ended up being stored in a transporter's buffer similar to how the episode "Relics" from Star Trek: The Next Generation, Captain Montgomery Scott (Scotty) is discovered alive in a transporter buffer after being trapped for 75 years on a Dyson sphere. The transporter has been rigged to sustain two life signals, allowing Scott to survive by maintaining a diagnostic cycle. His pattern remains intact, allowing him to be rematerialized after being rescued by the USS Enterprise. Another possibility is being back due to meddling from the Q or an evolved V'Ger. There's been published a comic where some of the old crew from multiple TV projects have been brought back to help solve the killings of some of Star Trek's Gods by an unknown figure. Emperor Kahless is eventually revealed to be Star Trek’s god-killer. Among the many cameos in the series are Benjamin Sisko, Jake Sisko, Kira Nerys, Odo, Worf, Alexander Rozhenko, Spock, Scotty, Uhura, B'Elanna Torres, Tom Paris, Ro Laren, and others like Q, Kahless (clone/Emperor), and crossovers with Picard-era or TOS characters. It does not have to be a TV series but could be a limited TV mini-series. The Star Trek financial gods wasted big money on a badly done Section 31 movie. I don't see why they don't do something more similar to Star Trek comic and Television canon.