Surely you don't mean to refute Hans Rosling's testimony that his mother had more time to read to him? I think you have an interesting viewpoint. If these technologies don't actually save any time, it follows that we spend as much doing X before the technology than after. So 4 hrs/wk washing 1 loads/wk + washing machine => 4 hrs/wk washing 4 loads/wk.

What if you reverse this and apply it to computers? I spend maybe 2-3 hours in Excel every week. If I were born 100 years earlier, would it follow that I'd also spend 2-3 hrs/wk making spreadsheets, albeit at a much slower work pace? It seems doubtful. I've got only a few dozen sheets, tops. Lots of time spent in Excel is tweaking, making things line up / look right, updating kludges, etc. Busywork, basically. Maybe this is my fault; the 'math' tells me I should have lots of sheets, but I get caught up doing busywork on this machine that's supposed to automate the whole ordeal. What a scam!