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

Execution · Light / Casual
An interactive wordless short story with essentially no skill test.

Execution · Light / Casual
A famously broken racer that tests nothing because nothing functions.
A Bird Story leans Execution (Light / Casual); Big Rigs: Over the Road Racing leans Execution (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
A Bird Story
Walking through scenes is the only input
Big Rigs: Over the Road Racing
Opponents never move; holding forward wins
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
A Bird Story
No opponent of any kind
Big Rigs: Over the Road Racing
There is no functioning opposition
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
A Bird Story
Wholly linear with nothing hidden mechanically
Big Rigs: Over the Road Racing
Nothing is hidden because nothing works
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
A Bird Story
Nothing to solve; it is a told story
Big Rigs: Over the Road Racing
No systems exist to solve - the game is unfinished
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.