head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Reads · Bluff & Deduction
The pack with Trivia Murder Party and Fakin' It, built on out-guessing the room.

Reads · Bluff & Deduction
The Quiplash 3 pack, where winning means predicting what makes this exact room laugh.
The Jackbox Party Pack 3 leans Reads (Bluff & Deduction); The Jackbox Party Pack 7 leans Reads (Bluff & Deduction).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
The Jackbox Party Pack 3
Phones-as-controllers, near-zero dexterity.
The Jackbox Party Pack 7
Typing and tapping only.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Jackbox Party Pack 3
Trivia Murder Party and Fakin' It reward reading the room.
The Jackbox Party Pack 7
Quiplash 3 and Talking Points are pure crowd-reading.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
The Jackbox Party Pack 3
Random prompts and question draws.
The Jackbox Party Pack 7
Prompt draws randomise every round.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
The Jackbox Party Pack 3
Light trivia and betting math.
The Jackbox Party Pack 7
Little to solve beyond wording instincts.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.