To your first question, yes I think it does. Government coercing my decisions is negative ( individually, not necessarily society/humanity ). In the same way, if government policy mandated televisions to be twice the cost because they deemed it hindered education, that would make me worse off as a consumer of televisions.

To your second question, I suppose I would argue that it lowers my standard living now, but _may_ raise the standard of living for posterity, since obviously climate change time scales are vastly greater than the effect of a tax now. However you could rightly argue that by UK citizens reducing their carbon footprint now, 3rd parties downwind directly benefit now by being less harmed by UK pollution, yes.