I’m sorry but it is a fiction that capitalist seizure of public goods are primarily intended to add value to “consumers”. If this does happen, it is an side effect, and I would argue a temporary one experienced while the system is coasting from the inertia of past public investments. You see the same thing with the victims of leveraged buyouts by private equity.
In the end without an ideological project that transcends personal or familial accumulation of capital, all collective enterprises are doomed to failure. This is because people alienated from the motive forces of the collective endeavor at some point stop caring about the forward motion of a system that at best only marginally and diminishingly benefits them.
The public sector is unfortunately a terrible place to pursue ideological projects. Especially in a democracy where the ministers with leadership authority of a department change every 2-3 years and very wide groups of stakeholders need to endorse any substantial change.
In general public services exist as public entities because they would otherwise necessarily be monopolies, and the only lever the public can therefore have is some kind of democratic process.
In the case of UK privatisation it’s clear that the policy was merely a wealth-pump designed to extract value from a captive set of consumers.