Those updates don't need to be heavy if nothing is happening. And as I related elsewhere, with a Ruby-based game engine it took 1000+ objects being updated eve

Those updates don't need to be heavy if nothing is happening. And as I related elsewhere, with a Ruby-based game engine it took 1000+ objects being updated every frame alongside other heavy stuff (multi-voice waveform based on-the-fly sound-synthesis, in Ruby) and actually passing each of them to the renderer, before I needed to bother to add any filtering. And then when I did need to it was a trivial change to filter the list of objects to update. To the point where I literally just currently naively every frame does a map over every object in the level and check if they're within the viewport before doing the update. Yes, you will sooner or later hit limits, but 1) you're likely to hit them later than you think, 2) it doesn't matter because when you do hit them you're likely to have a good idea of what characteristics to filter them by. E.g. for some games you want to update, but not render, objects outside the viewport in many situations based on other measures - e.g. Minecraft-style simulation of mobs within a certain distance of the player; for other games once an object is off-screen it can cease to exist instantly. But it takes consideration, and you might as well defer that consideration until you need to, because it's orthogonal to the actual update.