I think it is way less this than a constant reminder of “Hey, I could do that!” There are lots of people that don’t want to interrupt the gameflow and are thinking stuff like “Is this something I’m uncomfortable or am I just a wuss now? I mean, noone else says anything and they seem like they have fun…”, in some cases almost everyone in the group thinks that and noone says anything about it, leading to basically noone having fun in the end.
Of course it’s still sort of handhold-y, but it’s easy when playing with people you don’t know (or only barely) to offend them and scare them away because of something so trivial - like describing an abandoned home with spiders everywhere vividly to a person with arachnophobia (and to stress this point, the telling person does not know about that). Especially if the spiders are purely atmospherical.
Or if you know people rather well and there is some gruesome scene like Torture and there’s some fingernail pulling involved, I for one would immediately nope out of that - but not by telling people, but by pulling back from the play and trying to distract myself with something else, like thinking about how to develop my character next, which is easily misconstrued as “Hey, that guy isn’t fazed by that. Let’s nock it up another notch”