I stopped wearing a tie  to work at the start of 2004. It was summer and I was hot.
Its much more comfortable working without a tie, particularly in my job. Its easier to examine patients, its easier when I need to perform a medical procedure. I’m sure you can see how a dangling tie would get in the way.
I’ve also lost quite a few ties, sadly enough, to spillage, followed by dry cleaning. Dry cleaning and silk ties don’t mix well. The tie comes out worse for wear and never again, does it look quite right.
I wonder then how people clean their ties? I guess that the answer is that they don’t.
A tie could possibly be a source of infection. Imagine your doctor seeing patient after patient, either in the hospital or in their rooms, with that dangling tie.