One of my main peeves—aside from the general which I mostly avoid with TSA Pre—is a hiking pole which I often want to use at a random destination I’ll just use carryon for. But it’s not allowed in carryon.
The rules really are ridiculous. You aren't allowed to bring a clear bottle of water, but you are allowed to bring fish in your carry on. Freeze that water, or put a fish in that bottle of water, and it is allowed, because you're transporting live fish! I was going through a checkpoint a few weeks ago and forgot a filled, reusable water bottle in my backpack. Instead of just letting me dump the bottle out and proceed, the TSA handler made me go to the back of the line and go through the entire checkpoint, body scanner etc again. If I had just brought a fish with me, I could have avoided the whole thing.
[0] https://www.amazon.com/gp/product/B07VN5LRYQ No longer for sale, but there are similar ones
The TSA allows for breast milk and "toddler drinks" to be brought on board, with or without children present.
They also allow contact lens solution, liquid medication, and, during covid-19, hand sanitizer (an accelerant!).
Since the final decision rests with the TSA officer.. maybe.. just maybe you can sweet talk them and they'll allow it since it is _just_ a hiking pole.
Otherwise, agree. What an annoyance.