As someone whos used gym treadmills extensively (lots of icy roads around) I can say 100% of every direct interaction I’ve had, has been positive and from lots of different locations too. Lots of people (over a long period of time, so maybe every 15-20th time I went) come up and say it’s hard to fathom how fast I run (2:30 marathoner, so far from world class) or inquire what I’m doing or if I’m training for anything, and generally seems genuinly interested/happy I’m going fast.
The only negative things I’ve experienced is stares, sometimes because the treadmills are noisy (not my fault)