I mean, you're totally right (except for that last part), and 2023 was kind of frustrating for me. I didn't keep track (ratio-wise) of how much of my work got merged, but it feels like my success rate was around 20%. That's pretty depressing, but, on the other hand, it's also pretty encouraging: when I joined Bitcointalk, I knew jack-diddly-squat about SMF and I had never really used PHP in anger (when I'm working on things that I have architectural input on, which is most of the time, then I'll almost always reach for something with a better type system). PHP proficiency is easy to pick up, but SMF is difficult to untangle: internalizing all of its idioms and reasoning out the consequences of any given change takes a lot of time/effort (and a lot of testing).
20% may seem little, but in reality it is a lot of work accepted and many improvements made. I believe that not even in the biggest software companies can a single programmer get 20% of his individual work accepted. So I think that 20% should be very encouraging.
Furthermore, the more additions you create, the greater the difference in this percentage will be. Especially because 2FA alone is worth 10x more than many of your other proposals that were not accepted.
Regarding the OP's proposal, honestly, how many users would publicly display their network's contact details on their profile? Today, there is a very low percentage of those who share a link in the "website" field (which could be used to share a social network), let alone fill in the other fields. Therefore, I think it is not a necessary effort for this update. I'm not saying it shouldn't be done, just that it shouldn't be a priority. It's my opinion, of course.