In fairness, I partially understand the middle seat issue. There is never a good way for a gate agent to know what the passenger's underlying preferences are. Up until very recently, you could only opt in/out of C+ entirely with no seat preferences. I am sure many angry passengers have complained to the gate agent about a middle seat upgrade. So, it's a bit of damned if you do, damned if you don't situation.

Realize it will never happen and also create missed expectations/more drama, but really wish there was a custom-text "upgrade preference" note that would pop up right before an agent clears any upgrades to indicate actual preference. There's so many variables in play - for example, I will universally take 10B over any seat other than 10C, 19C, or 19D on a 739. If I am already in 19C/D, then my only upgrade option I would take is 10C. And if I have 10C, 19C, or 19D, then I don't want to get an upgrade to 1A if it is the only seat available but I would take an upgrade into any other F seat. Of course, writing this out only further cements the reason why it won't happen and also why gate agents often don't clear people into middle seats.. seat preferences are complex.