If you do go for competition cycling then maybe it is worth it to you to spend the extra $ but for the most part it seems to me that people just love to have an excuse to spend their $ to look like they are professional athletes.
Their bellies usually tell a different story, but fortunately for them lycra seems to stretch really well ;)
The only time I've had chafing issues was when doing a circle around the 'IJsselmeer' in one day. That was bad. But I was also peeing green and out for the count for the next day so enough time to heal up :)
Just need to find somewhere to store a road bike along with the skis, skateboards, snowboards, and mountain bikes now…
Another thing, if you're shopping for bikes is to check for new-old-stock, sometimes you can get crazy discounts on bikes that are only one or two years old thanks to the 'fashionista's' who wouldn't be caught dead on a bike that isn't of the latest model year and in the latest colors.
Carefully plot your routes.
> Lycra.
No need for that bs, a t-shirt, jeans and good shoes are all you need.
> The expense. A good road bike seems to cost ~10× more than a great skateboard or longboard (but about the same as an electric longboard).
You can buy great used bikes for relatively little money. I just bought a top of the line roadbike that's a bit older for $200 which I used regularly, another for $150, which I converted into a hometrainer:
https://jacquesmattheij.com/trainification
Don't fret about the quality of the bike, until you reach competition level it is totally unimportant. I regularly pass people on much better bikes with all the goodies and just yesterday I in turn was passed by someone in at least their sixties on a bike that was much older than mine and I wouldn't have been able to catch him no matter how hard I tried. The bike rarely matters.
> Friends who've had big crashes on the road; intuitively it feels like it should be safer than mountain biking, but I'm not so sure.
I've crashed pretty hard about 2 years ago. It was my own fault, riding a recumbent on a regular road. Still, I got lucky, broke my leg badly but nothing else.