With cheap energy, we could literally pull excess carbon dioxide, water and nitrogen out of the air and make fats, carbohydrates and amino acids. No need for agricultural land.
Yes, you absolutely can trap much more CO2 per unit of collection area with photovoltaics than trees can manage. The trees are cheaper per unit of carbon capturing capacity, but what they bind the carbon into is less useful.
That said, wood can be burned in such a way that only the hydrogen oxidizes, leaving charcoal that, powdered, can massively improve soil quality particularly in rainforests. Up until 500 years ago there was a thousands-of-years-long project doing this in the Amazon, interrupted by plague and collapse.
None are at scale yet. There is a lot of hand wringing about the cost (negligible compared to annoying Putin or OPEC), and some moral arguments from the greens about how it is unethical to expect our kids to spend electricity to clean up our mess (even though the cost of electricity production is currently dropping faster than it has in our lifetimes).