I'm a long-time DigitalOcean user and I'm happy with most of their products, but I use Backblaze for S3-compatible storage. It's half the price of Spaces, and I get better transfer rates from my DigitalOcean droplet to B2 than I get to Spaces, even within the same DigitalOcean datacenter.
There are tons of companies offering S3-compatible storage, and there's not much difference between them, other than price. Performance capabilities are similar; they all limit bandwidth. All the ones I've evaluated charge for egress over a certain threshold. Some are more reliable than others. For personal use, there's not a whole lot of difference between them for me.
One really cheap alternative for some use cases is Office 365. For $99/year, you can get a family subscription, which allows six accounts. Each gets 1TB of S3-compatible OneDrive storage. If you can handle it being broken up into six 1TB chunks, it's by far the cheapest storage out there. For comparison, Backblaze is $5/TB/mo, and Office 365 gets you $1.37/TB/mo. I didn't end up using this option because the authentication mechanism was inconvenient for my automated use case and I didn't end up needing so much storage, but it's worth investigating if you're on a budget and don't need automated access via e.g. rclone mounts (or want to take the time to overcome the authentication issues I ran into).
I evaluated about a dozen S3 storage options for both backups and as backing storage for a personal Plex server (of media I own) and eventually settled on Backblaze because it's cheap, easy to use, and I didn't need more than 1-2TB in the end (since not a single one can keep up with streaming video bandwidth needs, I ditched the Plex idea).