Also, worth pointing out that a lightning cable is $20 and they've only ever really made one. We're talking about bands as expensive as $449, with over 600 different ones released. It's a totally different subject.
It is a big deal, actually. We should all be vocal about our disdain for such a change. Shrugging it off as "oh well, no biggie, was fun while it lasted" gives them permission to do this.
I don't know about you, but I don't want my multi-thousand dollar band collection to be rendered obsolete in a year, locking me into old technology. It works with my current watch, yes, but what happens when my battery degrades, or the OS no longer gets support?
I've spent countless hours and, yes, way too much money on my collection. It's a hobby. I wouldn't collect them if they didn't work with the current watches. If Apple seriously changes the connector, I'm selling off every Apple thing I own and not looking back.
I see no probability that Apple completely axes the bands and retains no backwards compatibility with whatever new system they're designing. They know that would be a huge mistake.
Enjoying the moment is a nice sentiment, sure. But say you buy a car, then a year later you find out that they don't make the right kind of fuel for it anymore. Are you going to just go "Oh well, it was fun while it lasted. No big deal!" then buy another? Or would you be justifiably livid?