Yes, the bend is ideal but not required, just something that shows that you are trying to put something from the legs/core into the ball, even a circular rotation of the hips. You could even rotate the upper body a little to play the shot, but your arm won't get it done by itself. I was looking for an ancient video with cross backhand footwork but I couldn't find it. But there are many ways to do this, just about anything that feels as if weight is flowing through the hips in some form works, even the ones you think are incorrect. I have played backhands with my weight going in exactly the opposite direction from what I think is right, and I am at a point where on the backhand I have no clue what is right anymore from a quality standpoint.
In terms of quality, I find that sometimes, you need to find your swing and figure out what point on the ball works for your stroke. Keep testing different contact points until you find one that feels reliable and good to you to get the ball to do what you want it to do. And then just continue using it as long as it gives you the quality you are looking for. when I go down the line as a right hander, I always feel as if with my basic stroke I am hitting the left side of the ball. When I go cross court, I always feel like I am hitting the right side. It probably isn't that way in reality, but it gives me something to consistently repeat. and something I can use to calibrate my swing in practice.
Takkyu's comments about being too far away for the ball/not in the right position are spot on, though I differ a bit on solution. I would say that ultimately, it is a good thing to learn to spin the ball where it shows up when you have misread it, usually by contacting the ball on the side, rather than waiting for the ball with a technique that requires it to be at specific point, and then reaching forward. You have the backhand technique to spin it where it shows up, you just have to accept that it isn't going to be as direct as you might like, but put some more spin into the ball.
So I manage to watch the Liam Pitchford backhand masterclass and wow, I find out that like crappy old NextLevel, Liam Pitchford opens his racket, hits the left side of the ball and turns his wrist over the ball so that he has more contact area for a safe shot. I used to wonder whether I was doing something wrong by doing this and just like when I saw Gionis hooking forehands in his base warm up, I see Pitchford getting power and consistency using an idea I used to push but never really had the confidence to teach as a base technique when I coached. Well, those days are over now lol.
In the end, you have to balance what you know works for you with whatever you have been coached into.