Yes, this was the first series (racing cars or not) where the option to upgrade cars from within the career events was removed so far as I can recall. I’m also fairly certain you can’t upgrade them/download tunes from within the tuning menu either, as suggested by General Pretzel above. @General_Pretzel - if you disagree perhaps you could show us where in the following screens that option exists?
Regardless, no good reason has been given for this change. It just needs changing back and that shouldn’t require us to go off and create a “suggestion” to fix something that was working fine before.