There are viable competitors, but none of them are willing to offer dirt-cheap service like Cloudflare is, and that's really a shame. Fastly, akamai, etc. focus entirely on Enterprise and don't see making their product accessible to small business/personal project sites as a worthy business venture (which it probably isn't), so that leaves most SMB/personal sites the choice of either hoping they don't get attacked, using/paying for AWS/GCP DDOS protection, just not running their site, or using Cloudflare.