Agreed.
The defeat can be laid at the feet of Stuart.
Lee needed his cavalry. Without them he was fighting blind, could not disengage.
Stuart still has his fans, some of whom are down on Lee. See, for example, the essay Stuart at Gettysburg.
Your right and the earlier loss of Jackson crippled Lee.
Which brings us to.... George Armstrong Custer
His refusal to obey orders, instead riding to the sound of the guns.
And his blunting of Jeb Stuarts attack with his 4 Michigan units.
My understanding is that Lee also suffered dysentery, and was mostly confined to his tent and a nearby bucket. That is why he delegated the assessment of the artillery effect and the timing of Pickett’s charge to Longstreet.
Part of the reason for the failure of the artillery barrage was the decision to hold back some of the Union Artillery behind the hill, rather than exposing it to direct fire on the front of the hill. When the confederate artillery stopped, Union artillery could be run out to the front of the hill. Also the Union forces pushed small forces out to north and south of Pickett’s line of advance. The small forces provided a band of intersecting fire through which Pickett’s men tried to advance, at the quick (not double time, not in rushes).
Meade’s decision not to counterattack was the right one: Lee seemed to recover from his illness, and all the advantages of the defense would have been his if Meade had aggressively countered.
If Mead had put a corps with cavalry support to Lee’s south, with orders not to attack but to stay to Lee’s south (so Lee would have had to attack) Lee could have been destroyed. Alas that had to wait until 1865 and the Union forces were south of Richmond and Petersburg.