Unless there is an alternative it can't be outdated, per definition. WireGuard is not an alternative in many cases. But I get your point, it might have design m

Unless there is an alternative it can't be outdated, per definition. WireGuard is not an alternative in many cases. But I get your point, it might have design mistakes (or implementations we would have done different today, while I think you are talking about IKEv1, not IKEv2), but no IPSec/IKEv2 server is left open for scriptkiddies to break, it's receiving updates when bugs are found and in this sense not outdated too. Unless you're using outdated crypto algorithms, but that's up to you. The NSA possibly has capabilities to break IPSec/IKEv2 anytime they want, but that's something we don't know about WireGuard either. If that's the case with WireGuard, it has design flaws too or bugs which aren't found yet. It's better to know about a design flaw and mitigate against it, then not knowing about it and not being able to mitigate against it.