FFS flying is stressful enough in general - but when you have specific events (the crashes) and specific evidence of corporate [corruption/concealment/negligence/malfeasance or whatever the truth is within Boeing] which detracts from the faith in the safety of their life critical product(s) -- it has just destroyed a fair amount of trust in the company and the industry as a whole.
Not to detract from your points, but if you have any inclination to anxiety, yeah flying is stress-inducing.
The valsalva maneuver seems to work the best for me but it doesn't always work and is often painful.
- The stress of getting to the airport on time, and finding transportation from the airport to my destination.
- Standing in line for security checks together with hundreds of strangers, all impatiently waiting and shuffling in line.
- Waiting until boarding begins, trying to relax but at the same time trying to check of the gate doesn't change at the last moment.
- Getting crammed in seats that are too small, and having to sit there for hours.
- The high-pitched noise of the jet engines works on my nerves. Noise-isolating earbuds or noise-cancelling work wonders for that, luckily.
- Changes in air pressure often hurt my ears, and it sometimes (when I have a bit of a cold) takes a few days to disappear completely.
- I get airsick sometimes, especially in rather strong turbulence, so turbulence stresses me out too. Fortunately there are medications that work pretty well.
Not a lot of that is caused by the flying itself. Taking the Eurostar across the Channel for example has much of the same unpleasantness. And I imagine flying in a private jet or a Singapore Airlines A380 First Class Suite (as in https://www.youtube.com/watch?v=_O2_nTt1N6w) can be very pleasant.
You're not supposed to fly when you have a cold. Any existing swelling in the sinuses or ears can result in long-lasting injury. Usually that means ruptured ear drums, but the sinuses can be affected.
Pilots with a cold certainly cancel their flights.
I once told a friend with a cold to cancel his flight and take a 24-hour bus ride. He laughed it off and flew anyway. When I saw him a week later, he was still in pain.