Is there a major architectural change that would lead to them doing so? As I recall the previous times they dropped support for older hardware was switching from PowerPC to Intel and switching to 64 bit only.
None that I know of. You're absolutely correct, and I was as clear as mud on what I was meaning. Rather - I said the opposite of what I meant.
What I should have said was that if this machine is being bought for programming on iOS/OSX, then the risk in buying a 3-year "old" machine, would lie in support for some of the OSX's future features.
Was it Handoff that doesn't work properly on 2011 machines, due to Bluetooth incompatibility? So going forward, if more if these get added, to increase interoperability between iOS and OSX, then it stands to reason that the mid-2012/2013's would lose out first. My entire reasoning is based on there being hardware differences between 2012 and 2014 machines - which really means I should've checked that before suggesting as much, but pretty sure there are... It might not make much of a difference, but I reason it to be something to keep in mind, given the use-case. Were this to have simply been to try out OSX, emails, some web-browsing etc., I think the cMBP remains the cheapest entry point, second hand - given its upgrade options.
[sigh. See OP wants to develop in Java - ignore everything I said!

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