1. Manhole covers are not heavy as fuck. They’re meant to be able to lift out. I’ve lifted far larger ones than this no problem.
2. This manhole cover is at most 30x30cm judging by OP’s foot, so weights at most a few kilos.
3. This is a small cover, probably covering a drain, not a hole to the centre of the earth. I have a few around the house. Cable tie, piece of string, lift it out no problem. You lift and slide it aside, it’s not going to fall in unless you’re a complete moron or drunk. If it does fall in, you pull it out, because it doesn’t weigh 100 kg.
4. If you’re worried that this would take your finger off, you’re the kind of person who should hire an electrician to change a light bulb.

Because 10lb is so heavy

They really aren’t that heavy. When I was little, maybe 5 or 6, me and my best friend went to a construction site (excavators and cranes, so cool), snuck around on there during off hours (probably super dangerous, but here I am) and took some metal hooks, made from that metal grid stuff they use often in construction.

We then went and opened the actual manhole covers in my backyard with them, and even climbed down there (not that interesting, basically a few meters deep, with a small open sewage line running at the bottom).

Long story short, two pre school boys could open them by themselves in the 90s

If that were an actual manhole you’d be right, but its obviously not.

1. No
2. No
3. No