“But what if Joe Hooker had not been rendered ineffective by that artillery shell?”
No one can say, just speculate.
I will say this: getting a concussion was probably the worst thing that could have happened from the Union view.
If Hooker had been killed, a replacement commander would have been appointed. He probably could have done no worse; maybe better given the overwhelming Union advantage.
Grant (if he had been there; he wasn’t) would not have hesitated to take another 20,000 Union casualties in order to inflict another 2,000 Confederate casualties.
It’s fascinating studying all of the Generals in the East before Grant took command of all Union forces. They had overwhelming numbers and equipment, but were overly cautious, outmaneuvered, and outsmarted by Confederate Generals for the most part until Meade at Gettysburg. You are 100% correct that Grant would have thrown everything he had at Chancellorsville. Mary Lincoln called him a butcher, but he did what others before him refused to do to ultimately win the war.
Which brings up an interesting point, often overlooked.
At Chancellorsville itself, Lee's force was less than half the size of Hooker's, and yet Lee suffered more casualties and deaths than Hooker's forces.
22% of Lee's 60,000 troops were casualties = 12,764 including 1,665 killed in action.
9% of Hooker's troops were casualties = 12,145 including 1,082 killed in action.
Numbers & percents change somewhat if you consider the whole Chancellorsville campaign.
By my count, Lee lost two generals killed and nine wounded.
Hooker also lost two generals killed, plus three wounded.
Here is one description:
But he paid a terrible price for it, taking more casualties than he had lost in any previous battle, including the Confederate defeat at the Battle of Antietam.
With only 60,000 men engaged, he suffered 13,303 casualties (1,665 killed, 9,081 wounded, 2,018 missing),[11] losing some 22% of his force in the campaign—men that the Confederacy, with its limited manpower, could not replace.
Just as seriously, he lost his most aggressive field commander, Stonewall Jackson.
Brig. Gen. Elisha F. Paxton was the other Confederate general killed during the battle.
After Longstreet rejoined the main army, he was highly critical of Lee's strategy, saying that battles like Chancellorsville cost the Confederacy more men than it could afford to lose.[75]"
Bottom line: in Civil War battles, attacking forces often suffered disproportionately more casualties and that certainly included Lee: