To be fair, this will be fixed by browsers when it's within spitting distance of the scale of numbers setTimeout is normally used with. (not huge numbers) Like, if it's close enough that setTimeout(() => {}, 5000) will stop working a month later, that would be a major failure on the browser vendor's part. Much too close for comfort.
But I totally understand it not being a priority if the situation is: setTimeout(() => {}, 500000000) not working in X years.