OpenVPN can also be configured to operate a near line speed. It all depends on the underlying hardware, software, and configuration you're using.

Without being more specific in those areas and benchmarking the best reasonable configuration of one tool against the best reasonable configuration of the other tool, and then holding the rest of the factors constant, you've created a completely implausible and unsupportable conclusion.

I'm not saying that WireGuard isn't faster. I'm saying that you have done a poor job of describing how it is faster, and pointing to benchmark references to back up your claims.