head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is optimization, and it is a single point.

Optimization · Pure Optimization
A story-first adventure with gentle item-puzzle logic as its only test.

Optimization · Pure Optimization
Telltale's episodic comedy adventure sending Guybrush Threepwood after a pox plaguing the Caribbean.
Back to the Future: The Game leans Optimization (Pure Optimization); Tales of Monkey Island leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Back to the Future: The Game
Telltale point-and-click, zero dexterity
Tales of Monkey Island
Click-driven; no physical demands.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Back to the Future: The Game
Characters follow the episodic script
Tales of Monkey Island
LeChuck and pirates are pure script.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Back to the Future: The Game
Puzzle solutions are hidden until found
Tales of Monkey Island
Modern design telegraphs most puzzle information.
Back to the Future: The Game leans a little harder on optimization, though the gap is small.
Back to the Future: The Game
Light item-logic puzzles drive each episode
Tales of Monkey Island
Episodic inventory puzzles each have one intended solution.
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.