Yes, quite familiar with the Kangaroo appellation for vodka and vermouth.
As for "high rye" bourbon versus "low rye" rye you would probably be hard pressed to find a regularly available bourbon with more than about 36% rye (MGP) or Four Roses at 35% so the difference is more like 15%.
But that said I do prefer the higher rye content ryes for a Manhattan and only use the Rittenhouse/Sazerac "Kentucky style" lower rye content ryes when I have no other alternatives. But even then I feel it has a bit more rye flavor (especially the new Rittenhouse) than most high rye bourbons. And MGP ryes are now readily available most places. As is perhaps my favorite, the CEHT rye at least locally, which also appears to be a fairly high rye mashbill, maybe 90%, if a bit pricey.
Pre prohibition ryes from what I have read seem like they were more like the MGP 95% rye mashbill. Maryland style was perhaps a bit less but much more than the current "Kentucky style" low rye content ryes. Barton at one time made an 80% rye that High West has bottled and is excellent (the now dusty 16yo). Not sure it is being made any more by Barton though. The Canadian sourced ryes like Whistlepig, especially the barrel proof Boss Hog, and LSB work also but tend to make a pricey cocktail. The old Jefferson 10 Canadian sourced rye is a bit limited by proof and these days who knows where the newer bottle comes from or what is in it!
Another unfortunate legacy of prohibition I suppose that nearly killed authentic high rye content rye whiskey.
That yella whiskey runnin' down my throat like honey dew vine water and I took another slash…
Nullum Gratuitum Prandium
Ne Illegitimi Carborundum
I hate scotch.
Call it, name it what you want but if you ever try OGD114 in a Bloody Mary you'll never go back.