This doesn't seem unreasonable, OVH is not advertising DDOS protection (nor do they seem to be structured to offer it). Some hosts will can your VM and throw out its data, which is a much worse outcome.
Edit: I stand corrected ¯\_(ツ)_/¯
Edit: I stand corrected ¯\_(ツ)_/¯
And they also have a lot of experience with it because they host a lot of game servers which are very prone to DDoS attacks (see e.g. https://securityaffairs.co/wordpress/51640/cyber-crime/tbps-...), so they are definitely “structured to offer it”.