why do older consoles still work after all this time

[RaMon90]

Pretty much that.
Electronics these days are specifically manufactured to break after their warranty has ended.
It entices people to buy more instead of clinging onto old equipment.

I know that in certain televisions, heat sensitive parts are purposely put next to heat emitting parts.

It exactly happened to my samsung 32' tv, after warranty ended the hardware inside fucked up. I can say that not every elettronics break easily, for example after 4 years my other 50' lg still working even if you look closer you see the shadow of the previous channel logo. It's not visible from 50 cm distance, not a big deal.

However there's this warranty extend till 4 years if you add extra money like 50 to 80 $.
With this said i do agree that sometimes they don't produce with high quality materials.

 

[FAST6191]

On TVs then in some ways the industry is more incestuous than the car one ( http://www.monitor.co.ug/Business/A...o-industry-/688614-2272688-jc9mq8z/index.html ) and most panels are made by one of a few companies, https://technology.ihs.com/407194/chinese-suppliers-shine-in-large-sized-lcd-panel-market-in-q1 for an older one, more modern ones are not much better as a few players dropped out since then. After the panel then sure you might have a slight difference in power board manufacture (though probably not a huge amount) and the choice of awful decoder board, though again possibly an off the shelf design, and maybe nasty embedded linux board that you sort of just about manage to compile a netflix viewer for to make it a "smart" TV.
The bezel and frame might be different though, so might the location of the control buttons and inputs.