Had AI been around in the 60s, might Brian have considered using it?
Since it's all hypothetical, I'll say yes - with exemptions.
Consider how Brian in his teens, after getting a reel-to-reel tape deck as a gift, was using that technology which at that time in the late 50's was pretty much a decade old, and that's it. We have home tapes of young Brian stacking his voice through overdubs to replicate the sound of his beloved Four Freshmen. Listen to Brian's trademark high-range vocals: It's damn near the same as Bob Flanigan, in tone, phrasing, and general overall timbre to carry the high voice lines in that vocal stack. It can be uncanny at times to hear Flanigan and compare it to a 60's Brian vocal, circa 61-64. But it isn't actually uncanny when we consider Brian modeled his voice and vocal technique after Flanigan's with the Freshmen.
So breaking down all notions of reality and the time/space continuum, if that young Brian were using new and developing technology at that time to recreate the vocal sounds of his favorite group, why wouldn't it be probable that if a technology existed which would allow him to recreate those vocals as the AI programs are doing now, he'd be at least messing around with it and experimenting? Let's call it "analog Brian", and say if he were trying to have his own "Four Freshmen" in the form of overdubbing himself on a reel-to-reel in his teens singing other material, why wouldn't he do the same thing if another tool existed to do that same thing?
Remember that fragment of Smile which became known as Dixieland? That was a vocal game the Boys used to play in the car and elsewhere where each voice would riff on improvised lines like a Dixieland jazz combo, with the voices as the instruments. Now if tech existed where Brian could actually manipulate what those voices were doing and actually have the voices turn out sounding like a clarinet, trumpet, etc...don't you think he would have at least tried it?
Brian's willingness to work with new technology, new techniques, and new ways of recording music throughout the 60's and into the 70's is sometimes left out of the discussions. One of his favorite albums is and was "Switched On Bach", if that adds anything to the discussion. A totally "new" sound using one of the first commercially available Moogs to exist, and I think it inspired Brian's use of synths well into the 70's where some would consider him like a pioneer of synth-based pop tracks with the Love You album.
If a new technology came out that allowed him to experiment with sound, I'm sure he'd be all in. Would he use it on commercial recordings when he became a professional producer actually cutting records? Who knows...if it served a song he was working on, perhaps so. But if the teenage Brian was trying to recreate the voices and sounds of the Four Freshmen using the high tech recording device of its day, why wouldn't it make sense that he would experiment with similar technology if it existed.
