Sinadin
I have no idea why anyone would write an OP old man/hag (which is a female term, btw) in a ring/sharing souls/etc who makes ambiguous statements followed by never mind/you'll find out later/*insert obnoxiously smug statement here* to the (usually clueless) MC and typically tosses said MC into situations without warning or instructions, then mocks their progress or lack thereof. They are bloody annoying to read, and usually are largely involved in the story. I don't like to spend so much of my reading time being annoyed at characters and those who wrote them. The being annoyed at the writer is not just because those old men/women/creatures are obnoxious (because obnoxious characters can be interesting), it's the fact that they are so clichéd that they are flat (that is, lacking any depth or character) and cheap. (Note, "I am bored" is not an adequate explanation for their behavior.) This is a big, red, blinking, warning sign that that story will probably not even reach the average level of stereotypical "pathetic, downtrodden young mc gains ability/system/cheat to rise and become OP" stories, let alone rise above them. So I stop reading.
After thinking about this, and the fact that the MC should hate the guts of whoever did this to them, but they never do, I had a thought. I want to read one of these types of novels but where the MC has semi-realistic reactions after something like this "tutorial". They are stronger physically, but traumatized, with PTSD (aka post-traumatic stress syndrome, quite likely after dying multiple times) hate the old guy's guts and want nothing to do with them anymore, not even for the power being offered. So to get back on track, the old guy has to beg/plead, apologize, persuade, offer solice, help the MC heal (even if it's just a spell or potion to reduce the effects of trauma) and otherwise redeem themselves. In one variant, they do. But another satisfying version, they don't and (possibly even turn out to be the bad guy trying to ruin/train the MC), and the MC gets rescued from them by another strong being, who helps them recover, and get strong in a better way.