Is IKEv2 REALLY secure?

There’s been hype about how IKEv2 has been compromised by the NSA…

But, I use ExpressVPN on my Linksys WRT3200ACM router and their router app.

ExpressVPN uses an open-source implementation of IKEv2 , specifically Apple Dev’s IKE/ IPsec and StrongSwan on the server side, to ensure the integrity of the protocol.

Regardless of wether its an open source implementation or not, what makes IKEv2 technically LESS secure than OpenVPN, WireGuard, and other VPN protocols?

Please be as detailed as possible.