Is a standing desk worth it?

Yes, But...
It is all about posture. So, for example, if you slouch while standing and jut out a hip the same way over and over again, the effects will be detrimental. One pearl that I heard from an ergonomic professional/teacher was a doable formula of 20 minutes sitting, 8 minutes of standing, and 2 mins of moving around. Changing positions, proper posture while sitting and standing, good ergonomic setup, avoiding laptops (or if impossible, get a remote keyboard to separate your self from the screen), and taking breaks (look away from screen to exercise your eyes) will all help.

I used standing desks in my classroom. My students are able to move more so that they can concentrate more at the tasks they need to complete. They also help with being more alert so that looking at a computer all day is less draining. I recommend them,

Anytime you can include variation in your day your brain is benefiting. The human brain is complex, dynamic and thrives on making new connections. This is our significant human advantage. Variation (physical, cognitive, creative, emotional) brings new information to your brain and creates new neural pathways. We can't predict how new neural connections will impact your reality but we know that they will. Whether the variation of standing rather than sitting brings your more comfort physically or helps you solve a problem you have been wrestling with we can't know. Why not give variation a chance to work its "magic".

They say sitting is the new smoking! I don't have a standing desk but I have a standing piano :) but I am a singer (as well as a Reiki practitioner) and years ago I raised my keyboard so I am standing to pound notes when I'm learning music, and I much prefer that.

I think a standing desk is great way to work with integrating more continuous daily movement. I've been standing while working for many years. It took some time to work up to being able to stand the entire day, but now I can't imagine anything different. Keep in mind your metabolism doubles from sitting to standing yielding improvements in focus and energy. There are a lot of great desk options out there. Good luck!