People flew headfirst into double, or even triple Artemis, even after the Artemis nerf, which only made the gun and projectiles a bit slower, making it harder to hit with while the damage was the same. They also used the Blenderfish almost non-stop, which didn't stop Gat/Mortars from killing, especially when there was a second ship around with the same killing power, and Pyramidion's had the armor around the balloon to make it harder to hit it.
The probably biggest argument against the Goldfish was, and I quote a few too many people to name, "Why disable, when you can just kill them instead?" #DoubleJunkers (Ducks), #DoublePyra (Ryders) #SpirePyra (Thralls, but I admit, I am sure they flew other stuff too, but as far as I am aware, this was their primary ship combination back at that time; And their Pyra/Blenderfish failed against the Mandarian's double Junker). So the Goldfish was essentially thought to be quite useless. Why disable one ship, while the other is killing your ally and what if you fail because your heavy gun gets disabled in two seconds? Get two kill ships, focus your fire and they drop faster than you!
Btw, similar reason why the Squid was barely taken, on top of that it was slower than today after it was nerfed, because it was too fast in the beginning. People used it to disable and the only gun combination that was thought to be able to kill anything was Gat/Mortar, which the Squid was not particularly good at, because of gun arcs, so they stuck to disable on it. And the Banshee was different back then, I don't remember if it actually did more or less or even the same amount of hull damage as today. A disable Squid in the killing Meta wouldn't work so well.
The changes that made the Goldfish more viable was a different playstyle and the fact that a lot of people don't take double long range ships anymore, such as double Junker. With enemies having to close the distance themselves, they were doing half the work for the Goldfish, the Goldfish could then afford to wait in an ambush position or had much less distance to close before disabling the enemy. When was the last time you saw a double Mobula fight against a Goldfish with a long range ally, much less see the team with the Goldfish win that match?
Everything in the Meta was a reaction to the previous Meta and the people who flew it. With the Mandarians gone and the super long range sniping Gents deceasing, nobody was left to, well, snipe, at least with both ships on the same team. You can watch the Hephaestus Challenge, which came after the Sky League and then the R&D Invational, which came after that. You will see bits and pieces of the old mindset appear here and there "Let's sit and snipe for 2 hours, because fun!", but ultimately the Pyramidion was the most taken ship, so the Meta evolved around it, ships that synergize well with it, ships with forward facing guns like the Spire, Mobula and the Goldfish, all of them capable of brawling to some extent, shifting the game to close range. Out of those three, however, the Mobula had the same capabilities had as the Junker: Multirange combat, locking its position in the Meta, while the Spire got pushed out even further as it could do nothing against the long range fire and didn't have the Goldfish's speed to close the distance without dying or the ability to get in cover as easily, now that people actually flew it correctly. But the Pyramidion was still dominant, so people took the Goldfish to synergize with it in brawl maps, like Paritan and the Mobula for long range, like Fjords and Dunes.
After a nerf to the Pyramidion, people refused to take it back into competitive, leaving the skies to the Mobula and Goldfish. However, to the Goldfish dismay, double Mobula was popular and the Goldfish would have a place in that Meta, only surviving in various alleys of the remains from empty cities. People then experimented with the Squid, I think mostly after its buff, abusing its horizontal manouverbility to combat the Mobula that way, the one thing it wasn't good at. To synergize with the Squid, people went to the only fast forward facing ship that remains playable: The Goldfish, which was also used to counter the Squid's mobility as the Mobula didn't have that. And now we are here.
You may notice something missing in my ramblings, which I wrote without checking for corrections, so apologize if it isn't good or even wrong. The Galleon is not explained. The Galleon, in reality, has no place in the Meta and never will have, as Urz already mentioned it's competitive survival depends a great deal on the Lumberjack. That ship gets easily disabled from long range, close range and outmanouvered from all sides from everything! Yet, it is the living embodiment of "the one shot that matters", as each Artemis disable can influence an engagement a great deal and shift the advantage back and forth, the same goes for the Lumberjack, countering every ship in the game. The Galleon itself shifts the game away from the counters and tiers and more towards raw pilot and gunner skill, putting it into a weird spot. Not able to win anything at all, but proving again and again that it can kill anything it wants to.
