Modern programming languages abstract away both space and time: There is nothing indicating how long a called subroutine is expected to take or how much memory an allocated object will consume - even less so are there any ways to define constraints on those quantities.

It's the opposite actually: Object allocation is sort of a default operation that you do all the time, while deallocation has been abstracted away entirely and left to the garbage collector. Of course this will be extremely wasteful memorywise, but that's tolerated for convenience.

And that's not even accounted for all the inefficiencies which have become necessary due to security.