True, but he did not reject the overall concept. This is more an argument about details. Please note that as PM in the 1950s he made no attempt to dismantle or even scale back the system (which had only recently been established).
The NHS was (and still is) such a popular British institution that to dismantle the NHS even in 1951 would have been an utterly disasterous political move.
Even a move that would have led to actual public unrest.