“Engines” are not static things. What we call “Unreal Engine” goes back to the 90s.
These comments always bug me as a programmer because it’s like someone calling a 2023 Camero old because it doesn’t have the acceleration of a 2023 Mustang… The “age” almost certainly isn’t the problem, it’s where the effort has or hasn’t been put in to the engine and more importantly the game itself (e.g., carrying on the metaphor, the Camero might be slower getting up to speed because all the R&D for the last 3 years was on a smooth ride).