Are they? I don't know any factory workers but I have friends outside of tech and they can all relate to "arbitrary rules from management that make my job harder are frustrating".

The people who spend the most time sneering at 'the laptop class' that I'm aware of are independent, ie, non-unionized, tradespeople who operate as sole proprietorships - emphatically not factory workers. The arbitrary, unproductive distinction between 'real' physical labour of the kind carpenters, roofers, drywall technicians, etc, do and 'laptop labour' is increasingly being seen as exactly that.

If there are fewer cars on the road because the people who can work at home are doing so, then the commute becomes smoother for anyone who can't work from home.

Then they are short-sighted, because other people WFH would be better for them too. The US culture can be staunchly individualistic and bordering on revenge-oriented, so I can't say I'm surprised.