It's rude to keep checking it sure but not just wearing it. Self control is what matters. I shouldn't have to take off my watch in order to not look at it for an hour or two. If a person can't handle not being connected to the digital world, they have bigger issues.

Then 98% of apple watch wearers have bigger issues. I understand there is a huge self selection bias, but it is also understandable to glance at your watch when it vibrates, purely as a reaction.

I also agree it is not necessarily rude, if you do have self control. However, I think that wearing an apple watch at the dinner table is literally the exact same thing as having your phone at the table. It sends a message to the people you are dining with that you are ready to be interrupted by other people at any moment. At business lunch, fine. Socially - that is just rude. I don't care if it is standard - it is rude. I politely rib my friends with apple watches about this when we dine. I'm not a maniac - I am actually very polite and personable about this. But it drives me nuts, and while I understand I am myself being a prig about it, there is nothing more frustrating than talking to someone and they suddenly look away to read their phone in the middle of your sentence. The exact same is true with an iWatch.

Many, many more people will wear these things and engage in this behavior. It will not make them less rude. Politeness is an uncommon trait - and please know that I am perfectly aware that so much of this is totally unintentional and innocent. I have very high patience for this - most people just don't even think twice and actually feel bad if you raise the fact you don't love being interrupted by their phone. The vast majority of the time it is all good. That it is normal doesn't make it appropriate - our norms are below what I consider to be polite behavior. I'm not losing sleep over this, and I don't go around casting shade on people or thinking they are bad humans. I just am aware of it. I'm also never going to wear sweatpants to work, show up to the office smelling bad, pick my nose at the dinner table - plenty of things that are really not a huge deal but just off-putting to others around them.

the market for cheap mechanical watches is going to get smaller and smaller.

Maybe, but I doubt it. Most people who wear watches don't look at them and go "I wish this thing could show me my email." People who wear watches are not candidates, for the most part, for eWatches. People who already do not wear watches because they don't care about the time or think that having a celphone is an acceptable substitute are prime candidates. If watch sales are going down, it is correlated, not causal, with the rise of the eWatch.

Quite simply, people who care to wear a watch do it for a totally different set of reasons than people who care to wear an eWatch. They are about as similar as a sedan and a smartcar, or a station-wagon and a vespa. They are just totally, totally different products aimed at totally different markets. I think that the actual tradeoff numbers are going to be quite, quite low - though time may well prove me very wrong.