I can think of plenty of tasks where a 2009 frontend will potentially be exposed to workloads in the 10k-100k elements range: * Editing objects in a 3D scene(e

I can think of plenty of tasks where a 2009 frontend will potentially be exposed to workloads in the 10k-100k elements range: * Editing objects in a 3D scene(e.g. a AAA open-world game or a CGI film) * Plotting events in a long-running log on a graph * Scraping and presenting data from web sources The common thread here is that you have most of your data in application memory but not necessarily in a formal database system, and so you shoulder the full burden of managing it properly. In most cases the solution is to define a real backend and filter it there, paginate or otherwise reduce the amount that gets presented because data at that scale won't be usable by humans to begin with. But sometimes you do have a reason to explicitly want a "big list of everything," and equally as often you end up with the big list of everything just by accident. It just comes with the territory of report generation tasks.