Saving 500MB is worth, saving 100MB is worth, saving 10MB is worth. Memory has price of gold and many suggests to waste it. Definitely, it is your decision, if you want to waste it on your Mac, do it... And absolutely, it is very sad advice how to write very poor software.
Use https://pypi.org/project/memory-profiler/ to track your Python memory allocations. Use
x = someRamConsumingObject()
# do the stuff here ...
# remove the refrences
del x
x = None
gc.Collect() # try to force garbage collector to collect
Away from philosophical discussions, real examples from industrial Edge computing gives us exact reasons why this shall be improved. If running Python in containers one will soon hit the wall, especially having multiple containers running on the Edge under heavy production load.
And even if Edge has 16GiB, you will hit wall soon, especially using data analytics tools like Pandas.
Then, my friend, you will recognise what is the hell of garbage collectors and what means "not having memory under control".
C++ rocks!!!