I know what you mean, However, It is much better to dig it out, If you leave its root ball there, It will keep on growing back.
Fig wood is quite soft at this time of year, It is not hard to dig it out, Do u have reciprocate saw? you can use it to prune tree down till main branch left, Then dig around tree, and use saw to cutout all side roots, then shake the tree left and right, then it will come out with small root ball.
I plan to dig out 8 years old fig tree in size of 14x12 FT with thick body in next 1-2 year, and replace it with "Granthams Royals" - better fig trees for our area.
Even Roberto's fig tree, It grows shocking fast here in 2 year, It reach 12 ft x 6 FT size, If I am not able to taste its fig next year and see what quality of its fig, I will get rid of it.
Next year, I plan to dig out 2 in ground Chicago Hardy, I find that It needs high heat to ripen its fig with sweetness and our summer is too cool for it, I like high sweetness fig.
There are just too many varieties of fig trees, Pot culture needs lots of work, I trial them in pots, if It perform well, I would prefer to put them in ground.