I've been playing a lot of Baldur's Gate 3 lately and this kind of reminds me of when you have to roll a d20 in a skill check. Early in the game there are skill checks with a difficultly class of 2 (need to roll a 2 or higher to succeed) but you might have proficiency in that skill so you get a +3 modifier to your roll.

But if your base d20 roll result is a 1 then this is considered a critical fail and your modifiers are not added – you fail no matter what. So there is a 5% chance of failing no matter what (1 in 20).

However, you can have special items or spells which can grant you advantage in a roll: you roll 2 d20 instead of 1 and take the higher of each. Now the only way to critical fail is if you roll a 1 with both d20s. This has only a 0.25% chance (1 in 400).

So the "2 random choices" cache eviction policy feels kinda like rolling with advantage in D&D: Roll 2 die (pick to random keys) and evict the higher time since last access to evict.