You have a fair argument that my 5th and 6th level plan for a round expends the daily resources to be that competitive.Your Fighter sucks. He should have precise strike (ensuring he lands his GWM attacks) and tripping strike (for extra damage when he does land his hits, and advantage for the rest of his attacks that round due to Prone).
Also; slight problem with a Quicken build. While it works OK in really short adventuring days (1-2 encounters) it tends to suck on standard (6ish) or longer adventuring days.
Like... at 5th level (Sorc 3/ Lock 2), you have 3 SP. Thats 1 quickened spell per encounter (and you then need to blow a bonus action and one of your 2 second level spell slots to get those SP back to do it again).
Even if you somehow only managed to use 1 x 1st level slot for Hex (and maintained it all day long) you're left with 3 x 1st level slots, and 2 x 2nds (7 extra SP), not including your recharging Warlock slots (and even including them, that's 2 extra SP based on 2 short rests that day, considering you'll need to re-establish Hex after each short rest due to the 1 hour duration).
So at 5th level, you can quicken 5 (6 with 2 short rests) times (in an entire adventuring day (and realistically no more than 1/ encounter). That number drops with each spell you cast (like Shield), or each time you flub a concentration save and need to re-establish Hex.
There are also action economy issues. You'll be using a Bonus action to spam Hex onto your target, so no quickening that round. If you ALSO want to Hexblades curse, that's another Bonus action the following round (so again, no Quickening that round).
By Round 3 you can finally Quicken your (Hex+Curse) Eldritch blasts, but most combat are either over by then or nearly so.
At late levels (11th plus) you can reliably do this for the entire day for great DPR that lasts the entire adventuring day in most cases. But that DPR comes at the expense of your other spells, and you're still left with action economy issues.
I agree that casting Hex a second time greatly reduces the damage output. This is why I put so much focus on getting a decent AC, Constitution saving throws, Magical Resistance, and showcased it with a ranged attack. If I do get damaged with so few points to spend, there is little point getting hex back up for the few remaining rounds. For a fighter, he has very little to lose each round that would affect the next round other than being immobilized.
This build does have a reliance on good planning for how many encounters you estimate the day will last. However the analysis of Damage per Spell Point and Font of Magic enables you to pace yourself. The Fighter will easily out damage me the longer the day lasts. My quote of being better than the fighter should hold up past level 7 however as we have enough spell points to quicken almost every round.
Regarding the warm up time, most nova builds have this problem, which is why this build puts so much focus on buffing your allies. Those concentration spells are a great use of your first action. The second round of action is merely missing the hexblade's curse. At low levels this doesn't add very much, but I'm still doing quite a bit of damage. There is always Twin Command which trades raw power for hard control and action denial, which doesn't have a DPR to compare against.
Last regarding the Fighter build, let's say they go with Precise Strike and Trip. Given that the foe can simply get back up, he'd have to do this every round. The first attack is made at 60%, then we branch. Either he hit or didn't. Hits and our subsequent single attack and Attack action get advantage. If he doesn't does he spend another superiority dice to try again? How often will you riposte in an encounter? For my "80% better than a fighter" quote I was using this sheet made by another person. You'll need to head down to the "Fighter BM GWM GWF" section to see how they estimated the best strategy for maximizing expected damage.
I'll grant that the comparison isn't fair as these calculations assume the fighter is doing a reasonable balance between maneuvers, while my Sorlock assumes 2 targets I can touch and I add their damage equally.
Please do break down what a better fighter would do, using the same AC and HP as I used above. I'll gladly replace it. I'm going to block the human fighter however as an extra feat is not representative of a standard striker baseline.