I'm not sure when migratory beekeeping started here, probably after WWI and expanding after WWII, and after we had decimated most of the other populations of native pollinators with the mass use of pesticides in farming.
When I started my first hive in 2013 my beekeeping shop still stocked crown boards & telescopic tops and now it's just MG or the newer insulated one I'm adapting to. They thought I was pretty old fashioned because I wanted telescopic lol.
I don't find flat telescopic lids harder to work with if anything I prefer them, and I'm really not convinced that bees need upper vents all the time, I mean our MG tops were designed so the hives didn't melt down when stacked against each other on a semi during transit, not for backyard use. The hive that never had vents was always my strongest, I've only had problems since using MG.
I like the gabled ones cos they keep the rain off but they provide a place for ants so I might go back to an oversized piece of cement sheet on top of the lid with a spacer like I used to use.
Here's a very old film about our beekeeping industry, I do not understand how they are lifting three story hives off a truck so easily even if they have no stores, superhuman strength there!
https://www.youtube.com/watch?v=tJx4SYw78AsAnd another old but interesting report:
https://www.agrifutures.com.au/wp-content/uploads/publications/07-059.pdfAnd another (WA specific):
https://researchlibrary.agric.wa.gov.au/cgi/viewcontent.cgi?article=1259&context=bulletins