Furious and grief stricken over the loss of their beloved leader, the Mathosians blamed Orphiel Farwind and his Ethian scientists for the fall of Port Scion and swore to see their foul machines and Magitech devices destroyed in the hopes of stopping the madness as well as appeasing the gods.
In the alternate Defiant future, the Ascended did indeed destroy Meridian, the capital city that Orphiel and his followers had established to continue their study of the planes. The powerful Magitech defense system they had in place was destroyed, as well as any hope the Defiant had of stopping the Blood Storm. In exacting vengeance against those they felt had wronged them, the Guardians had doomed Telara. Soon after the destruction of Meridian, the dragons were able to break free of their prisons due to the weakening of the Ward. Since the Guardians were weakened themselves and had destroyed the Defiant machines, they didn't stand a chance against the combined might of the Blood Storm and were crushed. One last bastion of hope remained, a small underground bunker where a few desperate scientists continued their work of creating Ascended. Literally in the final days of Telara, when Regulos had all but devoured the world, the famous scientist Sylver Valis was able to finally discover the key to creating a successfully engineered Ascended made out of planar material and Magitech and fused with souls.
Even though this timeline didn't come to pass, due to the Defiant Ascended being able to use a time traveling device to return to a pivotal point and prevent the Blood Storm from taking over, the fall of Port Scion still remains an important key point in the history of Telara, the point where the fissure between those that followed the commands of the gods and those who wished to harness the power of the planes for their own use had become so wide that the two factions ended up in open warfare, fighting each other as well as the various enemies of Telara. The Guardians followed the Vigil and disdained the Magitech and the misuse of Sourcestone while the Defiant were ever curious and sought to discover the maximum potential of combining magic with technology and who did not have time for gods who were never there when Telara needed them.
In the proper timeline that we Ascended are involved in now, the Guardians were repelled at the bridge between Silverwood and Freemarch, Founder's Threshold, before they could step foot in what is now Defiant territory; Freemarch. The Defiant blew up the bridge rather than risk having the Guardians destroy all their valuable work. This forever created a rift, both figuratively and literally, between the Guardians and the Defiant. Their differing views, although always at odds, became full out war at this point.
Port Scion still stands between Freemarch and Silverwood, covered in tendrils of death magic and vines. It exudes the stench of evil and corrupts the very air around it. Nothing has gotten in or out since the moment it was sealed. Only time will tell if this will change.
I've also recently found more information on Port Scion located in an artifact set! The Twisted Artifact Set: Districts of Port Scion (lvl 65) from the Nightmare Tide content says "The grand city of Port Scion was so thoroughly destroyed the Endless Court that its districts don't even show up in nightmares." And than it gives a list of names, which I'm assuming are the districts. Freeholm, The Citadel, The Garrison, The Academy, Zareph's Plaza. I'm so excited to have some names of places in the city! Freeholm I'm guessing is probably their Inn or main Tavern. A place for traders and travelers to stay while conducting business. The Citadel is no doubt where Zareph rules and lives, conducting his royal duties and overseeing the smooth running of the city. I'm sure that diplomats and other important emissaries also visit and/or live there. The Garrison is obvious. That's Port Scion's army. The Academy has a magical item as it's icon so it's got to be a school or learning center, for magic perhaps? As well as other scholarly pursuits. Maybe it's a school that both southern tribal people and Vigil worshipping people can come together and learn things without prejudice or suspicion. Zareph's Plaza is no doubt the main plaza in the city, where markets, trade, scholars, merchants, and trainers can gather and discuss business. It's probably located inside the doors, in front of the Citadel, so that Zareph can keep an eye on things.
References: Well there isn't much information on Port Scion out there, but I dug what I could up! The first section is taken from the in game book "The Port of Scion". I'm not sure where I got the book. The rest of the section is written in my own words from quests in game and from information gathered on the forums about Rift lore. If I find out anything else I'll add it in later. Addition: The information at the bottom is gained from Twisted Artifact set Districts of Port Scion and just my theories of what it means. Normally I don't pay much attention to the Twisted Artifact sets, but this one seemed legit.