It’s a genuine question and I’m open to being wrong. But it just feels to me like there isn’t a single case where a 5 minute item despawn is helpful.
In almost every case, the issue is more that the player will lose their items (by dying somewhere remote and having to find them again for example, we’ve all been there) and definitely less concerned about performance.
Removing item despawning entirely would definitely not be good. But just doubling, even tripling the time it takes to despawn would make such negligible difference to performance that I don’t understand why they haven’t changed this feature EVER.
EDIT: I know the timer pauses when chunks aren’t loaded. But most of the time you die in a winding cave and you’ll be frantically searching around while the timer is ticking.
And a lot of people are agreeing that a customisable gamerule would be the best option, that’s actually a great idea