An easily visible one is air intakes. Many manufacturers have shifted to plastic. Peteo-engineering has advanced a lot, but they will still get brittle and break.
Interior wise, you can look at things like fabric durability-- lower deniers can be cheaper, but will wear sooner. Springs/foam in seats are another example, but this will vary across manufacturers, models and trims.
This isn't exclusive to financial engineering manufacturers like Stellantis or Nissan, either. Toyota has had issues with simple things like rust proofing (whether intentional or not) on 1st generation Tacomas leading to massive recalls and things like plastic timing guides prone to wearing out. Ford with the wet clutches having belts submersed in oil.
German cars needing body off access for rear timing chain maintenance at 80k miles. Water cooled alternators (really, VW?). All types of "why?" if you follow cars once they are 3+ years old.
It seems like there are a lot of regressions that probably result from cost cutting, while others may exist to simply drive service revenue.
Interior wise, you can look at things like fabric durability-- lower deniers can be cheaper, but will wear sooner. Springs/foam in seats are another example, but this will vary across manufacturers, models and trims.
This isn't exclusive to financial engineering manufacturers like Stellantis or Nissan, either. Toyota has had issues with simple things like rust proofing (whether intentional or not) on 1st generation Tacomas leading to massive recalls and things like plastic timing guides prone to wearing out. Ford with the wet clutches having belts submersed in oil. German cars needing body off access for rear timing chain maintenance at 80k miles. Water cooled alternators (really, VW?). All types of "why?" if you follow cars once they are 3+ years old.
It seems like there are a lot of regressions that probably result from cost cutting, while others may exist to simply drive service revenue.