The tax wouldn't be as effective as the ban
If your only goal is getting rid of the old bulbs, then, uh, yes - a ban is more effective. But I think there's legitimate reasons to prefer old bulbs for some uses, and even if I didn't I'm very skeptical of removing that choice. People make many choices that waste energy. People make all sorts of bad choices in a free society. Society has an interest in reducing those choices, but I don't think it's appropriate to eliminate this kind of choice. As an analogy, banning smoking would be "more effective" than taxing it (probably at least) but I think tax is a more appropriate balance in a free society.
The tax would need to be exorbitantly high for cheap-to-produce incandescent bulbs to be as expensive as the more efficient bulbs.
And? Are you worried that, uh, people will choose not to buy the old bulbs once they're more expensive? Are you worried that the government is going to get too much money? Anyways, yes, I agree the tax would have to be high in order to displace some old behaviors. That's the point, clearly. If people stop buying the highly taxed items, then society wins. If some people continue, then they win (by getting the stuff they want, for whatever reason) and society wins too (since the tax they've paid is going to way over-compensate for any extra energy use).
To be clearer, there's some tax number that represents a balance to the parties involved. A ban is effectively an "infinite tax". Infinity doesn't seem like the right number. Murder needs an infinite tax. Using an inefficient bulb... probably less than that.
It's also worth noting that, while current opposition to the "ban" is primarily from Republicans, the bill was passed by a Democratic Congress but signed by a Republican President.
It seems oddly natural for Americans to decide whether they agree with something by asking which party came up with the idea. I'm not American, and find this impulse really fantastically tragic. It's a good idea or it isn't, regardless of who came up with it.
So, the bill is not anti-consumer
Yes, it obviously, obviously is. For people that prefer the old bulbs, they've lost that choice. When someone can't get something they want, that's a negative for that person. That person, in this case, is a consumer. So it's a negative for some group of consumers. That's what anti-consumer means. A tax would also be anti-consumer, but it would strike a better balance between the interests of the bulb-buying consumer and the broader interests of society.