What would be the consequences for the western mediterranean basin, and beyond, with a Tartessian civilisation surviving the corner of the VIth century BC?
Let's assume (unless that's too implausible for a working TL), for the sake of the discussion, that Phoceans manages to win the Battle of Alalia, and that Carthagians are more focused on Thyrrenian Sea for the time being than closing the Iberic Sea to Greeks, maybe turning Tartessians into intermediaries.
What would that mean :
1) For Spain itself. How a maintained political ensemble (even with the possibility of Tartessos itself disappearing) would have changed things for what matters devellopment and sophistication of peninsular societies?
How important would be balanced indigenous and foreign (greek/carthagian/etrurian/campanian/celtic/etc.) influences?
Was it doomed into a peripherical role, or could it have became something greater?
2) For Carthagians. Without a monopole on Iberic Sea and Spain trade, would a more African focus for the punic society would have been possible (up to terrestrial trade along Sahara)? Or would the situation devolve into maritime wars?
3)For Phoceans. Would Massalia dominate the phocean ensemble in western Mediterranean, as it did IOTL? More importantly so, maybe? Or less, so?
4) In Gaul : how the devellopment of pre and para Celtic cultures and tribes would be changed? IOTL, the languedocians harbours were essentially a mix of Iberic/Ligurian/Greek/Etrusceans and later Celtic influences.
Would that be unchanged, or the Iberic influences would be butterflied/augmented?
5) Anything else you could think of, eventually.
Important
I know protohistoric PoDs aren't likely to give many clear answers, and that plausibility with the poor handful of informations that we have about the period (and how little of these made it into "amateur's history").
But let's avoid the usual trappings : "we don't know" or "everything would be changed and unrecognizable".