ENH: support 2D in DatetimeArray._from_sequence
Broken off from a branch that fixes #37682, the constraint on which is that _validate_setitem_value needs to handle 2D.
Thank you for weighing in Joris.  As I said in the OP, this is part of fixing #37682. hmm, yeah i think i agree with @jorisvandenbossche here, we should either go all in on 2D or not. can we just process column by column instead? > can we just process column by column instead?

we _can_, but it means putting more logic in Blocks which is the opposite of what im trying to do looking at this again it is fine. we do this in all kinds of places where we can potentially have 1d or 2d inputs.

unless objecting by @jorisvandenbossche and i think would need a concrete proposal that acheives the same aim, will merge tomorrow. this is fine