Is this DO specific? Aren't there other hosting providers with competitive rates, or is there something about DO that makes it especially good for this sort of thing?
If all you want are virtual servers (==droplets), DO is one of the more expensive options around. Of course substantially cheaper than AWS/Azure/GCP, but much more expensive than Hetzner/OVH/Netcup or anything on lowendboxes.com).
What DO has is some of the best content marketing around (great tutorials on server stuff) and scale. The first attacts beginners (which includes most of the spammers and hackers), the second puts them on people's radar.
The fact that there's an entire consulting industry around helping people figure out very basic pricing for very basic tasks on AWS should be a wake-up call that their documentation and calculators are awful.
Then again I'm sure there's no incentive to improve it, since if for whatever reason you were laid off from AWS... you could have a lucrative consulting gig the next day helping people with the blindingly obvious consumer pain points you refused to resolve.
I'm pretty sure one of the major reasons AWS is useful to large companies is that it removes prices and billing as far as possible from the place where you actually create resources. This enables people to just do stuff without the usual red tape involved in buying something.
If you want to see pieces as you do stuff you can go to the Google Cloud
While it’s less applicable to the VPS options, the open ended pricing of AWS and GCP gives people starting out or with very little monetary slack a lot of heartburn. And you do still need to have an account that covers the whole kahuna.
What DO has is some of the best content marketing around (great tutorials on server stuff) and scale. The first attacts beginners (which includes most of the spammers and hackers), the second puts them on people's radar.