I never really had an issue with inventory bloat caused by Eureka, as I don't hoard lockboxes (after every Eureka run, I hand them in. Usually only spending 10-20 minutes doing this, with plenty of inventory space to spare). Just because one person let themselves collect 10k+ lockboxes doesn't mean majority of the playerbase also does this (though to those who do: why? what's preventing you from handing them in in-between runs, or straight up tossing them?).
9 completely avoidable hours.