Again, 50k confirmed with all the documents. They might be dead, but there's no body, or the body can't be recognized, etc. Also I'm sure Mediazona doesn't have all the names, and their status.
Basically it's a process that takes time. If the war suddenly stopped today, I'm sure they would be finding and confirming more deaths for months if not years.
Ukraine is now supposedly capable of using light airplanes as kamikaze drones coming that far into the Russian territory. This is most probably an Aeroprakt A-22 Foxbat, a Ukrainian-produced light aircraft, equipped with an additional fuel tank and a remote control system.
You're right that the correct name is “Kerch Strait Bridge”. People call it "Crimean bridge" because it's just easier to understand for the people outside of the region. I think that's exactly the reason Kyiv Independent is using it as the name,just like Antonov bridge was called "Kherson bridge" for some time when it was in the news.
As for political meaning behind the name, I don't think there's any. I've never seen or heard any arguments about it neither in Ukraine nor in russian.
My uneducated guess is that it's just easier to say "Crimean" than "Kerch straight" bridge. Same in Ukrainian and russian. Also easier to pronounce.