I think there is a lot of value in it still.
It has little to do with conditioning in particular - board breaking can indicate that your striking point is conditioned, but it isn't used for conditioning.
Rather, it is a demonstration and test of focus and power. You can hit thin air and a bag all you want, but none of that demonstrates focus. Breaking a 12" x 12" x 1" thick untreated pine board is supposed to be the equivalent of breaking a human rib, hence the demonstration of power.
Selective breaks are interesting and bound to generate the most debate. I have practiced and accomplished several different types of selective break, this shows my capability at changing my focus and delivering power/energy to very specific spots.
One reason for discontinuing breaking is the price of wood and/or the difficulty of sourcing good breaking material. There are plastic rebreakable boards that you can get in various thicknesses which are a good replacement (depending on manufacturer their integrity is pretty good, i.e. they still take the same force to break on the 50th time as what they did when they were new, although you should expect some degradation over the lifetime of the plastic board).
So while I am a traditionalist, I still believe that breaking has an important role to play and shouldn't be discontinued (although it can be a good idea to re-evaluate the who/how/when of the breaking).