Motorcycles only seem cheap. Factor in a proper set of gear, like helmet, jacket, pants, and gloves, and you're up another $1k. Also note that maintenance intervals are more frequent. Consumables, such as tires, will be more expensive in the long run.
Why choose that over a used car for $5k? It's not cheaper, nor is it more practical. But I'll agree, on the nice days, it's definitely more enjoyable.
Are you comparing a brand new motorcycle with a 5k used car? You can get a used motorcycle and second hand gear. No matter how you slice and dice it, motorcycle is cheaper.
I can find several middleweight tourers / adv bikes between £12k-£25k new. And that's middle/top shelf. I can even get something new under £8k if I don't need the most modern electronics and 650cc is enough.
Comparing that to the car? LOL, 5 year used car like, say, Hyundai Ioniq is £15k+
And every other bit of the maintenance is more expensive in the car. Literally every single one. Also taxes and insurance.
Gear? Yeah, boots once every 10-15 years, gloves/jacket/trousers/helmet every 5 years,
Why choose that over a used car for $5k? It's not cheaper, nor is it more practical. But I'll agree, on the nice days, it's definitely more enjoyable.