I mean, that's a positive feedback loop. It takes longer to review, because they're expecting them to be big. Big PRs/MRs are left there until there's a big enough free time block to tackle and discuss. If the PRs are small, obvious things, they can be merged in minutes.

(Depending on what the PR's about and how the team organizes. Ideally, there's consensus on the goals or who's responsible for what. Reviews can be limited to finding bugs and e.g. organizational problems)