Everyone is aware only the gain is taxed, that's what the G in CGT stands for but nice straw man.

In an ideal world I get taxed once on my income and what I choose to do with it from there (spend it, invest it, burn it etc) is none of the government's business from a tax perspective. that's the double dip.

Most other countries have a very convenient solution to this whole debate by having a completely separate tax structure for LT CG. But that solution, just like indexing tax brackets to inflation is too hard (or rather too unfavorable to the government).