Nowadays you can buy a great bike for $1000 and be totally satisfied with it, ride it for years, or you can shell out $15000 for the top of the line model. And I'm talking about regular bikes, not e-bikes.
I paid 400€ for mine and it was the most expensive bike I've ever bought. And I honestly still consider that too much.
There's people who cycle as method of transportation, and those who cycle as a sport. It's only the ones cycling as sport who need this expensive stuff.
You don't get much bike for 400€ nowadays, maybe an entry level Decathlon model. I think I built my last classic road bike for a bit more than that amount out of a mix of second hand parts and a new cockpit, tires, chain and brake pads.
The city I grew up in and used this kind of bike just fine in has ~70m height difference between the hilly parts and the flat parts.
Sure, you won't be able to cycle up to the Zugspitze with it, but for cycling in a regular hilly town it's enough, 7 gears are fine and the brakes are good enough as well.
There's people who cycle as method of transportation, and those who cycle as a sport. It's only the ones cycling as sport who need this expensive stuff.