Why Do Modern Liberals Support Both Positive and Negative Freedoms?

Positive freedoms are the freedoms of individuals that promote the freedom of personal development and human flourishing without disrupting the development of other individuals. Negative freedoms involve the absence of constraints on the freedoms of choice.
Modern liberals seem to support positive freedoms more as it promotes the development of skills and talents within individuals without disrupting the development of other individuals. This means that constraints on the decisions we make do exist, however the constraints are to benefit society as a whole and provide some form of individualism within society, which can be linked with the ideas of freedom. In fact, Isaiah Berlin believed that people should be left to their own devices and has the ability to ‘be one’s own master’. Therefore, modern liberals support positive freedom as it allows individuals in society to be autonomous, but with suitable constraints which are required to prevent other individuals from flourishing and developing skills and talents. But, can having constraints and restrictions imposed on society contradict the ideas associated with freedom?
Although classic liberals prefer the ideas related to negative freedom, modern liberals see the advantages of this form of freedom as well as they believe that every individual should be entitled to as much freedom as possible and this includes the removal of constraints and external restrictions imposed by governments. In fact, it was J.S Mill that believed that it was unacceptable for society to accept and follow restrictions as it meant the absence of freedom. Therefore, modern liberalists such as Mill can support the ideas associated with negative freedoms. Nevertheless, could the absence of restrictions make members of society unaware of the consequences when making decisions that could severely impact other individuals in a negative way?