I don't see dismissiveness either; I see people telling the OP that this kind of behaviour is not something that one's co-workers should have to make accommodations for if she can't control it in a professional setting, because it is unprofessional. Lots of people who aren't pouring out sympathy have also made suggestions as to how the OP can minimise it, while saying the onus is on her, not her co-workers.
She knows it is her responsiblity to figure out what to do. That's why she is here.
Okay, most of us get it - that she/OP knows it's her responsibility to figure out what to do. We also know that's why she started the thread - to get advice and suggestions. There is no need to tell everyone 'why she is here' OP has done a good job of speaking for herself.
(However, some other people have said that people at the worksite should modify their behavior.)
Was the snark necessary?
I don't think oceanus is being snarky, or dismissive. I think many are letting Mom21son's popularity cloud their honest opinions.
Ok for me, I struggled with commenting on this thread. I read it when it was posted but waited a few days and until about 3 pages of posts to join in. why? Because I
like Mom21son. Shes a regular poster, shes smart and insightful and helpful. I didn't want to come out and post my initial reaction, because it was, in my head, pretty harsh. So I didn't post anything. That plus the mirror solution was suggested pretty early on, and I think that will help a lot.
So of course because many posters like the OP they want to naturally 'take her side' against the mean ol' supervisor who lost her patience. But... that doesn't mean the person who needs to change is the mean ol' supervisor. The OP's reaction is inappropriate for her setting. The supervisor should to have to approach loudly. She shouldn't sneak up on tip toes carefully avoiding the creaky spot in the floor like a kid playing a trick, but she should not have to announce her approach. Its really actually not reasonable. Its cool (and weird, quite frankly) that other co-workers do, but its not really anyone's issue but the OP's. And its really possible the co-workers aren't making noise for OP's sake, they might being doing it
for their own sake because they too have lost patience with the OP's startle response and its either make noise or yell at her themselves and they just don't want to deal with it.
We have had over the years countless threads about loud co-workers. And for that matter loud walkers in other areas of life. Its generally universally agreed adults should not stomp or make unnecessary noise, that learning to navigate life more quietly is the better way to be. Its not fair to now, simply because we like the OP, to do an about-face on that stance and start in with "well yeah its totally those quiet people, who are considerate of 99% of the other employees in the workspace who are at fault, people should bug all their other co-workers with unnecessary noise to accommodate you Mom! Buncha meanies!"