Mine then:

I think the meta will be: AST+SGE

My reasoning: I think players will also go into endwalker thinking "We need a buffer and a pure DPSer" rather than just "We need a pure healer and shield healer." From this standpoint, it will be white mage competing with sage, and then astrologian competing with scholar. To satisfy this while maintaining heal compatibility, our options are "AST+SGE" and "WHM+SCH."

So, I think it we'll see the best results pairing a buffer and a pure DPSer, but I also think the latter combination isn't going to be even close to competitive. It basically comes down to "pick the weaker/stonger pure DPSer" and "pick the weaker/stronger buffer", and "strong buffer + strong pure DPSer" seems like the winning combo to me.

Factors that might subvert my prediction: If AST buffs end up significantly weaker than expected, or chain strat ends up significantly stronger than expected, since I think DPS contributions will be the most important in determining the meta. It's also possible healing will be less equal than I expect, so maybe that will be a factor over DPS (But I think WHM still won't do well there due to MP management issues).