I don't dislike Wallach as much as some folks, but I'm not sure I'd say he's as good a fit as he once was. Reason being that they don't do any Wallach bits anymore. When I started listening to T&R 10-ish years ago, they had the big Wallach head, the bird stuff, him playing the clarinet, Shazowie, Walldick, etc. I can't remember the last time they did a Wallach bit, I think it's been years.I agree. Wallach is a great fit for the show, he has his place and it's better that he's there. Replacing him with a AI Bot isn't going to help anything.
If he's just the update guy and occasional interloper to conversations he's not really bringing much to the show.