No, gas taxes were always seen as part of conservation measures as well, especially since the 1970s. I see this claim all the time that gas taxes are purely a use tax, and that hasn’t been true for about half a century or longer, and just about everyone knows this, so I consider that kind of claim to be dishonest.
And yes, it’s less efficient than a carbon tax, but fundamentally you cannot deny the net effect of getting rid of the conservation aspect of gas taxes BEFORE passing a compensating carbon tax would have the effect of basically eliminating a carbon tax.
In other words, let’s talk about adding compensatory EV fees AFTER passing a carbon tax. Sounds fair and certainly better for climate.