Actually he was, those explanations invalidate Avalon, Excalibur, the actually ability for ubw to be a trump card (it's not anymore when you do the math) and even Gilgamesh's fortitude. He went from being powerful but beatable to unkillable because there's no longer a way to take advantage of his ego.
I think you're misunderstanding something a bit here. Those explanations don't really change much. We already knew Gil was powerful enough to steamroll the competition and win the Grail War by himself. Problem is, if Gil doesn't think you're worthy of his awesomeness, he's not going to fight you at full power. At all. The only exception was in UBW, when Shirou got the upper hand, and Gil was pretty much in a losing situation. And by the time he decided to pull Ea, it was too late.
The only time we see him going all out was against Iskander in Zero. Yes, Gil is pretty much unstoppable if we take everything he has into account. But his ego means that he will almost never fight at full power, so all those skills are a moot point unless he deems his opponent worthy.
Which, given what you've mentioned about Gil and Toshi's relationship, is pretty much guaranteed
not too happen.
He has items that are the same as Avalon and Excalibur, not copies or originals but items that produce the same effects as powerfully if not more so, having an unlimited number of swords is UBW's one advantage over the gate but that doesn't matter because if Gilgamesh is disarmed the weapons just return to the gate instantly so it can't beat Gilgamesh even conceptually anymore.and apparent CCC added some new crap about his endurance and crap so he's even tougher. And new super phantasms as well. So nothing works anymore. Look I know the ignorant people who never paid attention missed this but in the original version Satoshi had a hell of a time winning a fight. A rebooted Satoshi cannot win and even if Archer, Shirou or Saber could still win it's pointless. That means anytime Gilgamesh is a threat Satoshi will have to be saved by someone, last I checked heroes who are saved by their parents aren't good protagonists even slightly.
Again, only uses stuff if he deems it worthy. To the point where he only fired four weapons at Caster's giant monster, after Tokiomi begged him to do so. And then refused to get the weapons back because they had been "soiled" by being used on the creature.
And UBW, in theory, doesn't get the weapons back, but produces them fast enough that he
can outgun GoB. Again, that's how Shirou beats Gil in UBW.
And again, his endurance and powers are not new. We already now he's THE strongest Servant. His ego still remains as his fatal flaw.
It's true that completely invincible villains are boring. Which is why good OP villains tend to have glaring flaws which can be exploited by the heroes to outsmart them. Gil's is his ego. Learn to use that well, and you can make interesting Gil fights.
