It's called sanity.
Because what we have now is working SO well.... /sarcasm
what we have now is still better than most but yes, most definitely, it could be improved.
The issues with central planning are way too vast to list but the philosophical argument I have against it is the individual is lost. When we can focus on what is best for the individual then society benefits, it's not the other way around. If we focus on individual needs instead of societal needs and how best to solve them then everything else takes care of itself.
How do I feed myself, how do I take care of my family, how do clothe myself are very valid concerns we all have. If the answer is to let someone else do it for you (or through our health and social services, let us show you how someone else can do it for you) the overall societal impact is negative, not positive. If instead we teach basic survival techniques in school like what compound interest does to you at the pawn shop, why eating crappy food and laying around makes you unhealthy, why spending more than you bring in is unsustainable etc etc.
Focusing on societal needs while ignoring individuals leads us to record high poverty and a nation of takers.