head to head
Tom Clancy's Rainbow Six: Vegas 2 asks more than Red Dead Redemption 2, and the gap is execution.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.

Execution · Practiced Mastery
A cover-shooter Rainbow Six blending tactical room-clearing with solid gunplay.
Red Dead Redemption 2 leans Execution (Practiced Mastery); Tom Clancy's Rainbow Six: Vegas 2 leans Execution (Practiced Mastery).
Tom Clancy's Rainbow Six: Vegas 2 leans clearly harder on execution.
Red Dead Redemption 2
Gunplay and Dead Eye reward aim and timing.
Tom Clancy's Rainbow Six: Vegas 2
Cover-based gunfights still punish poor aim
Tom Clancy's Rainbow Six: Vegas 2 leans clearly harder on reads.
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Tom Clancy's Rainbow Six: Vegas 2
Multiplayer brings some human adaptation; AI is scripted
Tom Clancy's Rainbow Six: Vegas 2 leans a little harder on variance, though the gap is small.
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Tom Clancy's Rainbow Six: Vegas 2
Enemy placements partially unknown per encounter
Tom Clancy's Rainbow Six: Vegas 2 leans clearly harder on optimization.
Red Dead Redemption 2
Loadouts and routes solvable but loose.
Tom Clancy's Rainbow Six: Vegas 2
Room-clearing order and squad commands are solvable tactics
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.