Read this thread and want to add my .02 .
There are differences between today and 30-40 years ago as far as tractors and consumer needs . Old iron engines were built with "years of usage " ratings . Todays are built with "hours of usage" ratings . There is a reason I see engines 10 years old or less being replaced/rebuilt , while seeing engines like in my 3210 untouched and still running strong .
Now , as far as consumers . Todays consumer is more apt to just want something that will mow and do minimal hauling etc . There are much fewer people with the "need" for the toughness of old iron . Why would they pay $9-10,000 for a tractor today to just maintain their lawn and haul around their flowers .
Lol , what I haul with my little 3210 , with the original 10hp engine , I would never imagine hauling with my dads "new" tractor for fear of breaking it . I pull around a cart rated at 1000#s , but loaded till the rims are practically touching the ground . And my little tractor never complains . I've pulled my full size 96 F150 around the yard without so much as a squeak from my tractor .
Old iron was made during a time when people used and "needed" quality . Today , people spend the money elsewhere , like SUVs and paying others to do the work rather than doing it themselves (think lawn care companies, tree services, etc) . Companies follow suit and build lower quality machines a) knowing they won't get as much usage (or as hard) , b) they know a big part of profit is parts and service .