That trunk is easily bent. Maybe just not in the manner you are accustomed to.
If you were to tie a piece of rebar to the base of the trunk, and then wedge a block of wood between the rebar and the trunk at the point where you want some bend, then run a guy wire between the rebar and a point on the trunk above the wood block. Slowly tighten the guy wire. The trunk will bend.
You could probably apply enough pressure by hand to bend the trunk. But then it’s difficult to tightened the guy wire all by yourself. Having someone tighten the guy while you bend is easier. Or, you could employ a jack. Tighten the jack, tighten the guy. Then tighten the jack some more, take up the slack on the wire. Repeat until you get the curve you want, and maybe a little more. Then let it sit for a couple years.
Protect the tree with pieces of rubber where the wires wrap around.