People who ignore fallen allies and are not resing them, most likely don't do it because it is very often used for ganking. So it may be based on people's past experience and at some point they were killed when trying to resurect someone.
They are afraid that if they will try to res you - they will end up dead next to you.
If I can rez you, I absolutely will rez you. Battle rezzes are exciting; one must apply all buffs and hots before attempting. Know siege reload timing and try to rez in the window. Observe seige red circle and move to the side, parallel to seige while staying in rez-range to force siege to change position or miss you entirely. Multiple seige complicates battle rezzing, healers and tanks can team up for those.
Fan of playing magblade since 2015. (PC NA) Might be joking in comments.
-->(((Cyrodiil)))<--
i have my main house (grand topal hideaway) listed in the housing tours, it has multiple target dummies, scribing altar, and grandmaster stations (fully filled out with current game), as well as almost every antiquity furnishing on display to preview them
in progress: acquiring mundus stones (currently only have the thief)
The danger when trying to rez someone is, always, that whoever killed them is still around, and you're not free to react while you're trying to rez, so they get several free hits in. Try to rez someone in a fight and the chances are high you'll end up lying next to them.