head to head
Neither is simply harder - they are hard in different places. Borderlands 2 demands more execution; Tharsis demands more variance.

Optimization · Systems & Chaos
Loot-shooter RPG built on gear chasing.

Variance · Systems & Chaos
Tests probability management as dice rolls repeatedly threaten a doomed Mars mission.
Borderlands 2 leans Optimization (Systems & Chaos); Tharsis leans Variance (Systems & Chaos).
Borderlands 2 leans clearly harder on execution.
Borderlands 2
Aim matters but generous hit feel
Tharsis
Assigning dice needs no dexterity
Borderlands 2 leans a little harder on reads, though the gap is small.
Borderlands 2
Enemies are scripted loot fodder
Tharsis
Disasters are random events, not an adapting mind
Tharsis leans clearly harder on variance.
Borderlands 2
Procedurally generated weapon drops vary
Tharsis
Dice rolls and event draws brutally dominate each turn
Borderlands 2 leans a little harder on optimization, though the gap is small.
Borderlands 2
Skill trees and gear math heavily solved
Tharsis
Crew allocation and risk math are the counterplay
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.