Eh. If people are sharing bosses, that means they don't care. I haven't shared a single EG yet, and I don't plan on it. There's no need for me to share EGs since it'll take a LOOOOOONG time to get to an EG that I can't take out. That's not to say that EGs can't get so strong that I can't handle them. I remember seeing some of the EGs that EvilAngel shared back when he still played. They had millions of HP, and I'd struggle with some of those.
If someone shares a boss, feel free to poke it. I don't usually poke at EGs because you only get one gift per EG poked. It's more gift-efficient to take down my own EGs. Not only do I get more EP for it, but I get two gifts for every EG I take down. If I poke an EG, I get one gift and usually significantly less EP per focus. EGs just don't usually give gifts that are worth it. Sure, I've picked up a few R-Gacha tickets and a bunch of SR Wilds, but I've also picked up a few hundred "1000 Peros." I'm much more likely to get a gift worth wanting when I get two cracks at them, and I need a good EP buffer for phase 2. I'm consistently pulling in 2 million EP/Day, but there's no way I'll get that during phase 2. SEGs give double EP, but single pokes still only give small amounts of EP. I will be so much less efficient, and the whales who can take down SEGs left and right will soar past me. Even if I keep up my modest EP rate, the people that get all the slayers (I'm not even going to spin the e-gacha this event) will make several times what I can.
To help put this in focus, this event is similar to Gambit. I made something like 13,000 trinkets for phase 1, but I rolled my E-gacha tickets for phase 2, and I ended up making 45,000 in the 2nd week. People with slayers will increase their EP collecting power by 2-5 times since SEGs have insane amounts of HP, and if you can take them down, you score hundreds of thousands (if not millions) of EP in a single hit.